research topics in condensed matter physics

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Condensed-matter physics articles from across Nature Portfolio

Condensed-matter physics is the study of substances in their solid state. This includes the investigation of both crystalline solids in which the atoms are positioned on a repeating three-dimensional lattice, such as diamond, and amorphous materials in which atomic position is more irregular, like in glass.

Vibration isolation could boost performance of near-infrared organic LEDs

The development of high-performance organic LEDs and other devices that emit near-infrared light has been hindered by seemingly fundamental features of the light-emitting molecules. A potential solution has been identified.

• Margherita Maiuri

Rescuing magnetic oscillations by microwave shocks

‘Two colour’ pump–probe experiments on yttrium iron garnet discs demonstrate how to harness dissipation of magnetic oscillations. This may have important implications for the use of magnetic materials for information processing.

• Takis Kontos

A quantum solid made of electrons: observing the elusive Wigner crystal

In ordinary materials, electrons move too quickly for their negative electric charges to affect their interactions. But at low temperatures and densities, they can be made to crystallize into an exotic type of electron solid — a phenomenon predicted by Eugene Wigner 90 years ago and only now directly observed.

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• Bose–Einstein condensates
• Electronic properties and materials
• Ferroelectrics and multiferroics
• Ferromagnetism
• Magnetic properties and materials
• Molecular electronics
• Phase transitions and critical phenomena
• Quantum fluids and solids
• Quantum Hall
• Semiconductors
• Spintronics
• Structure of solids and liquids
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• Surfaces, interfaces and thin films
• Topological matter

Latest Research and Reviews

Unconventional magnetism mediated by spin-phonon-photon coupling

Here Pantazopoulos, Feist, García-Vidal, and Kamra explore the combination spin, phonon and photon coupling in a system of magnetic nanoparticles, and find that it leads to an emergent spin-spin interaction. This interaction is long-range and leads to an unconventional form of magnetism that can exhibit strong magnetization at temperatures very close to the critical temperature.

• Petros Andreas Pantazopoulos
• Johannes Feist
• Akashdeep Kamra

High-temperature concomitant metal-insulator and spin-reorientation transitions in a compressed nodal-line ferrimagnet Mn 3 Si 2 Te 6

The coupling between topological electronic properties and magnetic order offers a promising route for magnetoelectric control with great potential for both applications and fundamental physics. Here, Susilo et al demonstrate the rich tunability of magnetic properties in nodal-line magnetic semiconductor Mn 3 Si 2 Te 6 using pressure as control knob.

• Resta A. Susilo
• Chang Il Kwon
• Jun Sung Kim

Mechanism for sound dissipation in a two-dimensional degenerate Fermi gas

• Krzysztof Gawryluk
• Mirosław Brewczyk

Tunable magnetism in titanium-based kagome metals by rare-earth engineering and high pressure

Rare-earth engineering is an effective way to introduce and tune magnetism in topological materials. Here, titanium-based kagome metals RE Ti 3 Bi 4 ( RE  = Yb, Pr, and Nd) are synthesized and characterized, whereby changing the rare earth atoms in zig-zag chains the magnetism can be tuned from nonmagnetic YbTi 3 Bi 4 to short-range ordered PrTi 3 Bi 4 and finally to ferromagnetic NdTi 3 Bi 4 .

Unconventional superconductivity without doping in infinite-layer nickelates under pressure

The authors theoretically study the pressure dependence of the phase diagram of the nickelate PrNiO 2 with and without Sr doping. At high pressure, they find that the superconducting dome is significantly enhanced in both T c and doping-range of superconductivity compared with ambient pressure, with a maximal T c of 100 K around 100 GPa in absence of external doping.

• Simone Di Cataldo
• Karsten Held

A V 3 Sb 5 kagome superconductors

The family of A V 3 Sb 5 kagome superconductors provides a fascinating platform for the investigation of the interplay between superconductivity and charge-density wave order. This Review discusses the properties of the anomalous charge-density wave and superconducting states observed in these materials and surveys future directions in the study of these and related kagome metals.

• Stephen D. Wilson
• Brenden R. Ortiz

News and Comment

A voltage-balanced device for quantum resistance metrology

The quantum anomalous Hall effect holds promise for quantum resistance metrology, but has been limited to low operating currents. A measurement scheme that increases the effect’s operational current is now demonstrated — a scheme that could also be used more generally to improve the performance of existing primary quantum standards of resistance based on the conventional quantum Hall effect.

Enhanced generation of magnonic frequency combs

As counterparts to optical frequency combs, magnonic frequency combs could have broad applications if their initiation thresholds were low and the ‘teeth’ of the comb plentiful. Progress has now been made through exploiting so-called exceptional points to enhance the nonlinear coupling between magnons and produce wider magnonic frequency combs.

Sub-cycle photonics in correlated materials

Sub-cycle confinement and control of phase transitions in strongly correlated materials are theoretically demonstrated, potentially providing a way to investigate electron dynamics on timescales previously unattainable with these materials.

• Eleftherios Goulielmakis

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Condensed Matter Physics

Condensed Matter Physics (CMP) is by far the largest field of contemporary physics—by one estimate, one third of all American physicists identify themselves as condensed matter physicists. CMP studies the “condensed” phases that appear whenever the number of constituents in a system is extremely large and the interactions between them are strong.

Learn more about research in this area.

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Condensed phases range from normal solids and liquids to the Bose-Einstein condensate found in certain atomic systems at very low temperatures. Other examples include superconducting phase exhibited by conduction electrons in certain materials, or the ferromagnetic and antiferromagnetic phases of electron spins on atomic lattices. More recently “soft” condensed matter systems including polymeric, colloidal and biological materials are also categorized in CMP.

CMP is frequently associated with materials research, an application-oriented interdisciplinary field which involves the study of the synthesis, properties, and structure of a wide range of materials, many of practical or technological importance. The field draws contributions from CMP, chemistry and engineering and, more recently, from biology.

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Condensed matter physics is one of the most diverse field of physics, covering everything from mechanics to optics, quantum mechanics to statistical physics to quantum field theory. Condensed matter interfaces with devices and applications on the one side and has most recently come close to merging with biological physics.

Experimental Condensed Matter Physics

Moore’s Law is the observation that computing speed doubles every 18 months; we expect our computers to become smaller, faster and cheaper. In the last few years, Moore’s Law appears to be reaching its physical limit. Electronics cannot get any smaller. Physicists at the University of Utah are conducting fundamental research on materials that could hail the next advance in electronics: organic semiconductors, non-linear optical solids, high-Tc superconductors, spin electronics, quasicrystals, etc. The University of Utah is recognized as a leader in developing techniques for understanding the properties of these materials, including atomic force microscopy and tunable infrared lasers. Our condensed matter experimentalists also study other exotic materials, such as hyperpolarized noble gases, atomically thin materials, and low temperature quantum solids. View the current experimental condensed matter physics faculty .

Theoretical Condensed Matter Physics

Research topics of the condensed matter theory group cover essentially all problems of current interest: transport and optical properties of disordered interacting electron systems, 2-D electron gas with spin-orbit interactions, physics of graphene, the integer and fractional quantum Hall effect, correlated electron systems, quantum phase transitions and various frustrated spin models. Transport properties of strongly correlated systems subject to various external perturbations are also being investigated. View the current theoretical condensed matter physics faculty .

Experimental Condensed Matter Physics Faculty

Eric montoya.

Eric is an experimental condensed matter physicist working in the areas of magnetism and spin physics. With expertise in sample growth and nanofabrication techniques, Eric focuses on magnetic materials and spintronic devices. Eric and his group study the impact of spin-orbit interaction on magnetization and spin dynamics, spin transport, and spin torques. His group is also interested in harnessing these effects for creating novel spintronic and spin-orbitronic devices.

Research Website

Valy Vardeny

Valy's research areas include transient steady state optica and electronic spintronic properties of organic semiconductors in the time domain from femtoseconds to minutes.

Andrey Rogachev

Andrey spans topics in mesoscopic superconductivity, magnetism, quantum phase transitions, superconductor-insulator transition, nanoscience, nanotechnology, electron transport, noise in disordered systems, structures devices, and precision measurements.

Research website

Shanti Deemyad

Shanti is an experimental physicist, focused on studying the matter at extreme conditions of pressure and temperature. She is interested in several topics including correlated electron systems and physics of quantum solids.

Vikram Deshpande

Vikram and his group use low-temperature electrical transport spectroscopy to study nano-fabricated devices from Dirac materials to develop novel hybrid experimental tools, using high-frequency and optical techniques. Their goal is to explore the rich physics arising in these materials due to the combination of symmetry, topology, and electronic correlations. He and his group are also interested in potential applications resulting from the remarkable physical properties of these quantum materials.

Christoph Boehme

Christoph focuses on the exploration of spin-dependent electronic processes in condensed matter, including spin-dependent charge transport and recombination but also spin-injection and spin-transport in presence or absence of charge transport. The goal of these efforts is to allow for coherent spin motion detection of small spin ensembles as needed for materials research and single electron or nuclear spin readout devices as needed for quantum information science.

Theoretical Condensed Matter Physics Faculty

Mengxing ye.

• non-equilibrium dynamics and control in quantum materials, such as Van der Waals heterostructure and quantum magnets.
• non-Fermi liquid and quantum criticality
• correlated phases and responses in narrow band systems

Her research involves studying the interplay between symmetry, correlation and topology in various type of quantum crystals.

Oleg Starykh

Oleg's research focuses on frustrated magnetism, quantum spin liquids and strongly correlated systems with significant spin-orbit interaction.

Mikhail (Misha) Raikh

Misha works in the field of disordered systems. His research interest include spintronics, the field which studies spin transport and spin dynamics, e.g. magnetic resonance. His expertise with disordered systems has enabled him to discern certain delicate features of spin dynamics in a random magnetic field.

Eugene Mishchenko

Eugene's research covers topics in spin-polarized transport in low-dimensional systems, electron-electron interactions in one- and two-dimensional systems, fluctuations in mesoscopic conductors disordered optical media, and superconductivity of cold atom systems.

Research Experiences for Undergrads

The Department of Physics & Astronomy at the University of Utah offers a research experience program in physics and astronomy that allows undergraduate students to work closely with a faculty mentor and their research group on an individual project.

All interested students are invited to apply for this 10-week summer program.

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Condensed Matter at Penn

Condensed Matter physicists study matter in its nearly unlimited variety of condensed states from liquids to crystalline solids, from thin films to fabricated or chemically-synthesized nanostructures, from quantum Hall electron gases to superconductors, from carbon nanotubes to liquid crystals, and from amorphous structures to complex fluids.

The Condensed Matter research at Penn is organized around three broadly defined groups: Quantum Matter, Soft Matter and Living Matter.

• Condensed Matter

Condensed Matter physicists study matter in its nearly unlimited variety of condensed states from liquids to crystalline solids, from thin films to fabricated or chemically-synthesized nanostructures, from quantum Hall electron gases to superconductors, from carbon nanotubes to liquid crystals, and from amorphous structures to complex fluids. We seek both to clarify the fundamental issues behind the striking properties of these systems, and to illuminate their potential for useful application in many areas from electronics to biology and medicine. Condensed matter physics underlies many key devices of information technology, including the transistor, the solid-state laser, optical fiber, magnetic storage media, the liquid crystal display. The Condensed Matter research at Penn is organized around three broadly defined groups: Quantum Matter, Soft Matter and Living Matter.

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Rebecca W. Bushnell Professor of Physics and Astronomy

Randall kamien.

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Eugene Mele

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In condensed matter physics at Johns Hopkins, experimental and theoretical research programs are at the forefront of both hard and soft and biological matter. On the hard side, we study quantum magnets, superconductors, topological materials, magnetic nanostructures and quantum nanowires using a variety of experimental techniques, including neutron scattering, optical, and terahertz spectroscopy; synthesize and characterize new solid-state materials; and model theoretically novel states of matter such as topological insulators, Weyl semimetals, and quantum spin liquids. Soft and biological-matter research includes the dynamics of conformational transition in proteins, x-ray and neutron scattering studies of glasses and out-of-equilibrium complex fluids, biological applications of nanostructures and analytic and computer-aided theory of non-equilibrium processes, adhesion, and friction.

The Department of Physics and Astronomy is home to the Johns Hopkins Institute for Quantum Matter funded by the U.S. Department of Energy. At IQM, all stages of hard condensed matter research are conducted, from the synthesis of new materials, to their experimental testing and theoretical modeling. Our group takes advantage of the university’s high visibility in nanomaterials, biophysical, and biomedical sciences and bioengineering through numerous interactions and collaborations.

In addition, the JHU Applied Physics Laboratory has an extensive program in applied condensed matter sciences and is a leading center in quantum optics and optical quantum computing.

• Hard Condensed Matter Physics Facult y
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Condensed Matter Physics Research Overview

Condensed matter physics is a study of complex phenomena arising from interactions of many particles. It includes studies of solids, liquids, gases, plasmas, bio-molecules, etc., where even fundamentally very simple constituent particles (electrons, grain of sand, etc.) can lead to complex behaviors in systems consisting of ~10 23 particles.

Condensed matter physics is often motivated by the search for new materials with unexpected properties. It is an extremely active, dynamic field of research and is the largest subfield of modern physics, with over a third of the members of the American Physical Society being condensed matter physicists of one kind or another. In the last 20 years, more than 25 Nobel Prizes were awarded to condensed matter physicists.

In many systems, the constituent particles are well-described by classical mechanics, and the quantum-mechanical effects in their interactions can be neglected. Such systems are said to be subject of “soft” condensed matter physics. The word “soft” in this context does not have anything to do with the softness of the resulting material, but is just a proxy for the classical nature of the particles.

Example research topics in soft condensed matter physics being pursued in our department include:

• friction, fracture, adhesion and lubrication
• liquid crystals
• biological physics
• complex fluids

The theoretical and experimental tools of soft condensed matter physics are:

•  statistical physics
•  numerical simulations
•  study of transport phenomena
•  thermodynamical measurements
• optical / neutron / X-ray scattering

Quantum mechanics is required in order to understand the behavior of many systems, even when the systems themselves are macroscopic in size. For example, systems whose behavior relies on interactions between individual electrons, cannot be understood on the basis of classical mechanics alone. Such systems are the subject of “hard” condensed matter physics, where again the work “hard” does not imply that the resulting materials are hard in the everyday sense of the word.

Researchers in our department conduct investigations in many areas of hard condensed matter physics:

•  high temperature superconductivity
•  strong correlations
•  topological phases of quantum matter
•  quantum magnetism
•  Bose-Einstein condensates
•  nanostructures
•  quantum computing
•  synthesis of new quantum materials

The theoretical tools of hard condensed matter physics are:

•  quantum statistical and many-body physics
•  quantum numerical simulations
•  quantum field theory and non-perturbative approaches

Experimental tools are similar to those employed in soft condensed matter physics.

Theoretical Condensed-Matter Physics

Cornell set in place several keystones of contemporary condensed-matter physics. The renormalization-group approach to critical phenomena, the theoretical description of exotic ordered phases (inspired by the discovery of superfluid helium-3), and the defining textbook of our field (Ashcroft & Mermin), were all developed at Cornell. These keystones now serve as foundations for new and exciting areas of research at Cornell.

The renormalization group approach is now being applied to and developed for many new systems. Among classical systems, the onset of chaos in low-dimensional systems and spatially extended dynamical systems as well as hysteresis loops in magnets and crumpled paper are such examples. The renormalization group approach is serving as a key tool for studying quantum phase transitions in strongly interacting systems such as high Tc superconductors as well.

The theoretical study of exotic phases is taken to new horizons at Cornell. Ordering induced by disorder is being investigated through models of frustrated magnets that include effects of thermal fluctuations, quantum fluctuations and vacancies. Quasicrystals- exotic phases with pentagonal or icosahedral order coexisting with long-range, but non-periodic translational order are subjects of active research. Novel approaches and techniques such as large N methods are being applied to new “spin-liquid materials. Topological phases such as fractional quantum Hall states and topological insulators are studied in close connection with rapid experimental developments.

Strange and beautiful emergent properties of quantum matter are studied through concepts of order parameters, symmetry breaking and topological defects that originated from the theory of superfluid helium-3. Cornell has played a central role in the theory of defects in liquid crystals; it is now actively developing the theory of ”electronic” liquid crystals and their connection to high Tc superconductivity. Ultra cold atomic gases are new forms of such quantum matter. Under active study at Cornell are both classic phenomena including topological defects and fundamental new issues such as thermalization mechanisms.  Effects of quantum mechanics and interactions amplified by spatial confinement in mesoscopic and nano-scale systems are studied through close collaboration with Cornell experimental groups.

Computational condensed-matter physics is a growing area within the theory group. The development of elegant software design and algorithms are all emphasized. Examples include wavelets in electronic structure, design patterns in multiscale modeling environments and iterative constraint-based methods for image reconstruction. Graduate students can use such elegant computational methods to study everything from magnetic grain boundaries through simulating fracture and crackling noise, to extracting the three-dimensional structures of proteins.

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VIEW LARGER COVER

Condensed-Matter and Materials Physics

Basic research for tomorrow's technology.

This book identifies opportunities, priorities, and challenges for the field of condensed-matter and materials physics. It highlights exciting recent scientific and technological developments and their societal impact and identifies outstanding questions for future research. Topics range from the science of modern technology to new materials and structures, novel quantum phenomena, nonequilibrium physics, soft condensed matter, and new experimental and computational tools.

The book also addresses structural challenges for the field, including nurturing its intellectual vitality, maintaining a healthy mixture of large and small research facilities, improving the field's integration with other disciplines, and developing new ways for scientists in academia, government laboratories, and industry to work together. It will be of interest to scientists, educators, students, and policymakers.

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National Research Council. 1999. Condensed-Matter and Materials Physics: Basic Research for Tomorrow's Technology . Washington, DC: The National Academies Press. https://doi.org/10.17226/6407. Import this citation to: Bibtex EndNote Reference Manager

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Research in Condensed Matter Experiment (CMX) encompasses a broad range of topics and techniques designed to investigate the quantum properties of solids. These efforts aim at expanding the frontiers of knowledge of quantum systems and evaluating their potential as platforms for new quantum technologies.

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• Condensed Matter Physics

The field of condensed matter physics explores the macroscopic and microscopic properties of matter. Condensed Matter physicists study how matter arises from a large number of interacting atoms and electrons, and what physical properties it has as a result of these interactions.

Traditionally, condensed matter physics is split into "hard" condensed matter physics, which studies quantum properties of matter, and "soft" condensed matter physics which studies those properties of matter for which quantum mechanics plays no role.

The condensed matter field is considered one of the largest and most versatile sub-fields of study in physics, primarily due to the diversity of topics and phenomena that are available to study. Breakthroughs in the field of condensed matter physics have led to the discovery and use of liquid crystals, modern plastic and composite materials and the discovery of the Bose-Einstein Condensate.

CU Boulder faculty who study Condensed Matter physics are engaged in exploring the theoretical models of condensed matter, as well as experimenting with and observing the behaviors of condensed matter in a lab environment.

Condensed Matter Research Groups

• Experimental Research
• Theoretical Research

By putting theory to practice, our award-winning faculty use state-of-the-art technology to explore and observe fascinating phenomena at the quantum level. Faculty in the experimental condensed matter field work with primarily graduate and post-doc students in order to conduct research. Occassionally, undergraduate students are invited to participate in research activities.

Soft Materials Research Center

 Research is directed toward understanding and using the properties of condensed phases, ranging from experiments on the fundamental physics of phase transitions and chirality in liquid crystals, to the importance of liquid crystal ordering in the self-assembly of DNA and its role in the evolution of life in a pre-biotic earth, to the development of liquid crystal electro-optic light valves.

Center for Experiments on Quantum Materials

The CEQM investigates new materials with emergent quantum properties. The center combines the expertise of its fellows in materials synthesis, characterization, and control of quantum phases through novel experimental techniques. Center participants include the University of Colorado and neighboring institutions along the Colorado Front Range including Colorado State University, Colorado School of Mines, NIST, and NREL. 

We are interested in discovery and study of novel quantum materials that are driven by a combined effect of spin-orbit interactions and electron-electron correlation. Our research program encompasses a methodical search for new materials in single-crystal form, and a systematic effort to elucidate the underlying physics of these materials. Our group is equipped with (1) advanced techniques and comprehensive facilities to synthesize bulk single crystals of a wide range of materials, in particular, novel transition metal oxides and chalcogenides, and (2) a wide spectrum of tools for experimental studies of structural, transport, magnetic, thermal and dielectric properties as functions of chemical composition, temperature, magnetic field, and pressure. Measurements are often carried out at extreme conditions, i.e., ultralow temperatures, high magnetic fields and high pressures. We have also established broad collaborations with leading scientists in the US and around the world.

Dessau Group

 We use femtosecond optics and electron spectroscopic tools for the study of the electronic structure, magnetic structure, and phase transitions of novel materials systems such as high temperature superconductors (HTSCs or cuprates) and colossal magnetoresistive oxides (CMRs or manganites)

 My group aims to identify and understand new states of matters arising from interactions among multiple degrees of freedom  and strong electronics correlation.  We use the transport properties of quasiparticles and thermodynamic characteristics to investigate a wide range of quantum materials and their new phases, under high magnetic field and low temperature environment.

Lehnert Laboratory

 In our lab, we study the quantum behavior of small electrical or electro-mechanical circuits.

Reznik Group

 We use X-ray and neutron scattering to study electron properties of many exciting materials.

Rogers Group

 Our group is working on the nanoelectromechanical behavior of nanowires and fabricated electromechanical structures and surface/bulk molecular dipole systems.

Smalyukh Lab

 Our scientific interests encompass different branches of soft condensed matter and optical physics, including novel laser trapping and imaging techniques, molecular and colloidal self-assembly, fundamental properties of liquid crystals, polymers, nano-structured and other functional materials, as well as their photonic and electrooptic applications.

Raschke Nano-Optics Group

 We use and develop nonlinear and ultrafast optical scanning probe techniques to study domain formation, dynamics, and phase transitions in complex oxides, including ferroelectrics, and multiferroics, with emphasis on effects of reduced dimensionality and quantum confinement.

Ullom Group - NIST

 My research is focused on developing superconducting electronics for sensing across much of the electromagnetic spectrum. For example, superconducting sensors can be used for high-resolution gamma-ray spectroscopy, and for the detection of astrophysical millimeter-wave radiation from the cosmic microwave background. Current research projects include very basic topics (what is the resistance mechanism in thin-film superconducting sensors?) and very applied topics (the construction and delivery of complete instruments to various observatories). Devices of interest include transition-edge thermal sensors, kinetic inductance sensors, superconducting quantum interference devices (SQUIDs), and tunnel junction refrigerators.

Theoretical physics forms the foundation of modern physics. Using fundamental principles in math and physics, the faculty who explore theoretical condensed matter physics utilize hypothetical, mathematical models to calculate, explain and predict the behaviors of various and changing forms of matter. 

Center for Theory of Quantum Matter

 The CTQM conducts theoretical physics research focused on macroscopic quantum matter. This research area is a focal topic that transcends traditional discipline boundaries, unifying the otherwise disparate fields of condensed matter physics; atomic, molecular and optical (AMO) physics; nuclear physics; high energy physics; and quantum information science.

 My research interests are thermodynamics and statistical mechanics of condensed matter systems, phase transitions and critical phenomena, Ising model and other spin models, solid-liquid phase transitions, random materials, liquid crystals, Monte Carlo methods and pseudorandom number generators. I am also engaged in physics education research projects involving upper-division courses for physics majors.

Victor Gurarie

 I am interested in exact methods of statistical mechanics and quantum field theory, with applications to problems of quantum Hall effect, disordered conductors and insulators and problems arising in the field of ultracold atoms.

Michael Hermele

 My research is focused on strongly correlated quantum systems -- both in solid state materials and in ultra-cold atomic gases -- where interactions among the constituent particles produce qualitative effects. My interests encompass topological phases of matter, quantum criticality, strongly interacting quantum field theories, and a variety of specific systems including ultra-cold alkaline earth atoms, 5d transition metal oxides, and others.

Andrew Lucas

My group works at the interface of theoretical condensed matter, high energy, mathematical and atomic physics. We specialize in the study of dynamics in strongly interacting quantum many-body systems.

Rahul Nandkishore

 Complex many-body systems can display qualitatively new physics. The search for such emergent phenomena is a central goal of condensed matter physics. My research is focused on the search for new emergent phenomena in quantum many body systems with strong interactions and/or strong randomness. I work on systems both in and out of equilbrium. Particular topics of interest include (but are not limited to): non-equilibrium quantum statistical mechanics, many body localization and thermalization, field theory of correlated systems, Dirac fermions, unconventional superconductors, and the interplay of disorder and interactions.

Leo Radzihovsky

 I am interested in a broad range of condensed matter phenomena, just about anything, where interactions and fluctuations play a qualitative role. These range from rubber to liquid crystals and colloids, superconductors to quantum atomic gases and the quantum Hall effect, vortex lattices to charge density waves. Even if not always the highest hit on science citation index, some of this work has even inspired a song on  youtube .

Rey Theory Group

 Our research interests are in the scientific interface between atomic, molecular and optical physics, condensed matter physics and quantum information science. Specifically, on ways of developing new techniques for controlling quantum systems and then using them in various applications ranging from quantum simulations/information to time and frequency standards.

• Atomic, Molecular and Optical Physics
• Chemical Physics
• High Energy Physics
• Nuclear Physics
• Physics Education Research
• Plasma Physics
• Gravitational Physics
• Astrophysics and Planetary Sciences
• History and Philosophy of Science
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College of Arts and Sciences

Condensed matter physics.

Research in condensed matter physics covers a wide range of topics that include experimental studies of wide bandgap semiconductors and the nonlinear optics of organic solids along with theoretical studies of layered materials, defects in strongly correlated materials, and topological physics.

Experiment: Activities span from molecular materials, organic and inorganic semiconductors, wide bandgap semiconductors, point defects, and rare earth doping. Exciton dynamics in molecular crystals and organic semiconductors, including singlet exciton fission and triplet exciton fusion, is studied via pump and probe spectroscopy and fluorescence dynamics (I.  Biaggio ). Other topics include nonlinear optical spectroscopy (I.  Biaggio ); point defects in insulating materials with ferroelectric domain walls and other dopants; excitation processes of rare earth in wide band gap semiconductors, formation dynamics of single crystals in glass (V.  Dierolf ). 

Theory: Novel two-dimensional layered materials and their hybrids, heterostructures, and interfaces; Electronic and related properties of bulk semiconductors and insulators; Impurities and defects in materials including their interplay in strongly correlated materials/systems; The physics of carrier localization in model systems and real materials (C.  Ekuma ). Topological condensed matter physics, superconductivity, classical and quantum phase transition in strongly correlated and disordered systems, and field theory (B.  Roy ).

Related People

Michael Stavola

Professor Department Chair

Jerome Licini

Associate Professor

Chinedu Ekuma

Assistant Professor

Ivan Biaggio

Volkmar Dierolf

Jean Toulouse

All research areas.

Condensed Matter

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Atomic, Molecular, and Optical Physics

Atomic, Molecular and Optical (AMO) physics explores the interactions between atoms, molecules and light. Topics of intellectual emphasis within AMO range from the most fundamental questions in quantum mechanics to the study of emergent phenomena in many-body quantum systems. Rapid advances in the precision and control of spectroscopic techniques have led to numerous breakthroughs including the laser (Nobel Prize 1981), the atomic clock (Nobel Prize 1989), optical cooling (Nobel Prize 1997), and the optical frequency comb (Nobel Prize 2005). Current AMO experiments have demonstrated the most precise measurements of time ever made, achieved the lowest temperatures ever recorded, and attained essentially perfect quantum control over ever-larger assemblies of particles.

Modern AMO physics is also a highly collaborative field, characterized by strong links to other disciplines. Although AMO and condensed matter physics developed as separate fields and remain distinct, over the last 20 years deep connections and cross-fertilization have emerged. For example, as a result of the discovery of Bose-Einstein condensation of atoms (Nobel Prize 2001), AMO experiments have become fertile ground for discovering new phases of matter and exploring complex condensed-matter phenomena. Quantum computing was born in AMO physics (Nobel Prize 2012), and condensed-matter implementations of quantum computers are now poised to transform the way we process information. AMO experiments offer the possibility of deep connections to high-energy theory research as well: historically, it was the measurement of the Lamb shift in atomic hydrogen that heralded the onset of quantum electrodynamics, and modern precision measurement techniques are a major avenue for probing physics beyond the Standard Model.

The experimental AMO group at UCSB uses the full suite of modern tools for quantum control of neutral atoms, ions, and molecules to address a range of research topics, from condensed matter physics to tests of fundamental symmetries. Our group has strong collaborative links with condensed matter experiment and theory efforts at UCSB, and is developing connections with high-energy physics. Research efforts within the UCSB AMO group include:

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Andrew jayich, david patterson.

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Atomistic modelling of solid surfaces and 2D structures

Thermodynamic properties of atomic defects for quantum technologies, atomic scale manipulation for better electronic devices, molecular beam epitaxy growth of aluminum films for superconducting qubits, scanning probe microscopy of superconducting capping layers, identifying the charge generation process in organic solar cells, emissive processes in organic light emitting diode materials, modelling the light-emitting molecules/materials, design and control of quantum materials: metal organic frameworks (mofs), spin crossover materials, new types of particles in spin-crossover materials, organic-inorganic hybrid opto-electronic devices, organic semiconducting lasers, regulating phase transitions and formation energetics in metal halide perovskite-based optoelectronics, quantum theory of hydrogen bonding, light emitting field effect transistors.

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• Publications

In our group, we study the possibility of finding new physics beyond the standard model through atomic and molecular systems.  In particular, we exploit the capability of controlling internal degrees of freedom in molecules to propose novel detectors for searching light dark matter. In the same vein, we employ the remarkable precision of spectroscopy of atoms and molecules to constrain existing boundaries on different theoretical models regarding new physics.

Dark matter searches through atoms and molecules..

Observations from radial velocity curves in galaxies, galactic velocities in clusters of galaxies, and the temperature anisotropies of the cosmic microwave background (CM B) point towards the existence of  dark matter . Thereby, dark matter affects the dynamics of the universe on all scales: from the galaxy scale to the cosmological one. In particular, the CMB measurement established that around 24% of the universe's energy budget is in the form of dark matter, whereas only 4.6% is ordinary matter. In addition, astrophysical observations show that dark matter feels gravitational force, but they do not reveal any physics regarding the particle nature of dark matter. Therefore, experiments based on interactions beyond the gravitational force are needed to elucidate the ultimate particle dark matter nature . 

Dark matter detection scheme using CO molecules

                                                                      Energy budget of the universe

Our group studies atomic and molecular systems that  may be potential candidates to detect dark matter with mass below the proton mass. This is possible thanks to the energy scale associated with the molecules' different internal degrees of freedom. In particular, vibrational degrees of freedom in diatomic molecules shows an energy scale of ~0.5 eV. Therefore, assuming a typical dark matter speed of 600 km/s, the excitation of a single vibrational quantum in molecules will correlate with dark matter masses below 100 MeV. Indeed, this sensitivity to low dark matter particle masses  is hardly achievable by accelerator-based experiments. Therefore, our research is complementary to the ongoing research in the high energy physics community. 

High precision spectroscopy and the search for new physics

The standard model of particle physics is the most complete theory for the fundamental forces of nature except for gravity. However, it does not answer questions like: what is dark matter? or what is the origin of the neutrino masses? Thus, new theoretical models need to be developed and tested, which are known as physics beyond the standard model . As an example of physics beyond the standard model, we present the typical pair annihilation into two photons. In this case, one of the photons is dark, has mass, and decays into a pair of dark matter particle-antiparticle.

Decay of Ps into a pair of dark matter particles: particle and anti-particle

The spectra of atoms and molecules ultimately result from the interaction between hadrons and leptons. In our group, we study how atomic and molecular spectroscopy can elucidate the fingerprints of physics beyond the standard model . In particular, one uses the precision of the measurements to put constraints on different physics models beyond the standard model. Among the other candidates, we use exotic atoms like positronium (Ps) or muonium (pµ-).

Relevant publications

• Cold and Ultracold Chemistry
• Fundamental aspects of few-body processes in chemical physics
• Machine Learning techniques for AMO physics
• Physics beyond the Standard model through atoms and molecules

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• Complex systems

In real-world social networks, your enemy’s enemy is indeed your friend, say physicists

If you’ve ever tried to remain friends with both halves of a couple going through a nasty divorce, or hung out with a crowd of mutuals that also includes someone you can’t stand, you’ll know what an unbalanced social network feels like.

You’ll probably also sympathize with the 20 th -century social psychologist Fritz Heider, who theorized that humans strive to avoid such awkward, unbalanced situations, and instead favour “balanced” networks that obey rules like “the friend of my friend is also my friend” and “the enemy of my enemy is my friend”.

But striving and favouring aren’t the same thing as achieving, and the question of whether real-world social networks exhibit balance has proved surprisingly hard to answer. Some studies suggest that they do. Others say they don’t. And annoyingly, some “null models” – that is, models used to assess the statistical significance of patterns observed in real networks – fail to identify balance even in artificial networks expressly designed to have it.

Two physicists at Northwestern University in the US now report that they’ve cracked this problem – and it turns out that Heider was right. Using data collected from two Bitcoin trading platforms, the tech news site Slashdot, a product review site called Epinions, and interactions between members of the US House of Representatives, István Kovács and Bingjie Hao showed that most social networks do indeed demonstrate strong balance. Their result, they say, could be a first step towards “understanding and potentially reducing polarization in social media” and might also have applications in brain connectivity and protein-protein interactions.

Positive and negative signs

Mathematically speaking, social networks look like groups of nodes (representing people) connected by lines or edges (representing the relationships between them). If two people have an unfriendly or distrustful relationship, the edge connecting their nodes carries a negative sign. Friendly or trustful relationships get a positive sign.

Under this system, the micro-network described by the statement “the enemy of my enemy is my friend” looks like a triangle made up of one negative edge connecting you to your enemy, another negative edge connecting your enemy to their enemy, and one positive edge connecting you to your enemy’s enemy. The total number of negative edges is even, so the network is balanced.

Complicating factors

While the same mathematical framework can be applied to networks of any size and complexity, real-world social networks contain a few wrinkles that are hard to capture in null models. One such wrinkle is that not everyone knows each other. If the enemy of your enemy lives overseas, for example, you might not even know they exist, never mind whether to count them as a friend. Another complicating factor is that some people are friendlier than others, so they will have more positive connections.

‘Social networks’ could tease new particles out of collider data

In their study, which they describe in Science Advances , Kovács and Hao created a new null model that preserves both the topology (that is, the structure of the connections) and the “signed node degree” (that is, the “friendliness” or otherwise of individual nodes) that characterize real-world networks. By comparing this model to three- and four-node mini-networks in their chosen datasets, they showed that real-world networks are indeed more balanced than would be expected based on the more accurate null model.

So the next time you have to choose between two squabbling friends, or decide whether to trust someone who dislikes the same people as you, take heart: you’re performing a simple mathematical operation, and the most likely outcome will be a social network with more balance. Problem solved!

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Graduate Galileo Circle Scholars for 2024

Congratulations to the Galileo Circle Scholars for 2024! Our graduate students are passionate, and we invite you to read further on their current paths and research!

Anubhab Chakraborty "My name is Anubhab, and I am a 6th year PhD student in Physical Chemistry in the Department of Chemistry and Biochemistry at the University of Arizona. My principal field of research involves designing metal-organic solid-state systems and studying their properties at both a molecular and a macroscopic level with the broad goal of creating more energy efficient electronic devices.

Currently, I am working on surface alloy systems that exhibit Rashba spin-orbit coupling effects, which are ideally suited for applications in the emerging field of spintronics. I am planning to graduate soon and post-graduation, I would like to join organizations that address the issue of global energy crisis using technological breakthroughs on an industrial scale. I am grateful and humbled to have been selected as a recipient of the Galileo Circle Scholarship and I would like to express my deep gratitude to my parents and my advisor Dr. Oliver Monti for guiding me every step of the way."

Bai Hei Bai completed her BS in Chemistry in 2019 at Peking University, Beijing, China, where she contributed to DNA sequence analysis and coarse-grained chromatin model in Prof. Yi Qin Gao's group. She is now a fifth-year graduate student in Dr. Steven D. Schwartz’s group. Her current research focuses on computational studies for complex systems including ionic liquids and the human cardiac myosin, aiming to illuminate the atomic structures and energetics of these vital systems.

Lindsey Holmen "I'm Lindsey Holmen, a fourth-year graduate student working in Jeffrey Pyun's research group. I focus on synthesizing new polymers with tailored properties and exploring their applications in various fields like nanotechnology and IR device fabrication. I love being part of our interdisciplinary research team, where we collaborate closely with industrial partners and other research groups, integrating insights from various fields to tackle complex challenges and drive innovation.

I am also the president of PAWS (Program to Advance Women Scientists) where I participate and help execute outreach, professional development, and social events. Outside of the lab, I love to spend time with my two dogs and participate in outdoorsy activities. I am grateful for having been selected as a 2024 Galileo Circle Scholar. It means a lot to me and motivates me to keep doing my best. Thank you to everyone who has supported me."

Ramandeep Kaur "I am a 4th year graduate student in Dr. Gianetti's lab. I am originally from a small village in Punjab (India). In Gianetti's lab, my research is focused on the development of fluorinated carbenium ions and their applications in Lewis acid-assisted catalysis. In my free time, I love watching thriller movies and web series."

Christopher Marshall "My name is Christopher Marshall, and I am a third-year graduate student in Jon Njardarson’s research group. I earned my B.S. in chemistry at the University of Arizona. Following graduation, I worked as a formulations chemist at a biotechnology company in Tucson. After working for three years, I decided to pursue a Ph.D. in organic chemistry, specializing in synthesis and the development of new synthetic methodologies."

Joohyung Park "I was born and raised in Seoul, South Korea. I fell for science in my high school days, the quantized nature of atomic states during chemistry class mesmerized me and it led me to chemistry major at Chung-Ang University, located at the center of Seoul. Learning modern physics in my first year of college then led me to take a double major in physics, focusing on the physics of inorganic chemistry and condensed matter. Aside from classes, I also served friends and people in the department as a student representative for two years. After finishing my third year, I did my military service for two years.

Being isolated from the civilian world, I had many opportunities to look back on myself and decided to study more in graduate school. I did my master's degree in materials chemistry, mostly focusing on chemical methods to synthesize thin film transistors. My dire curiosity to study more physics then led me to study electronic structures of solid-state materials, especially in the US. There I started my new journey at the University of Arizona in Fall 2018. Working for Professor Monti, I learned how to become a critically thinking scientist, deep knowledge of physics that I hoped to learn, and I also had incredible chances to use state-of-the-art instruments around the world to study the exciting nature of quantum materials.

Teaching undergraduate students as a teaching assistant, especially 6 years of teaching the 400B courses, also made me a better educator and better mentor - and I have been proudly teaching 400B as a Distinguished TA since 2023. Overall, the journey to become a Ph.D. under Professor Monti and the Department of Chemistry and Biochemistry so far made me grow up to an unsurpassed extent in my life. I aspire to continue working as a scientist; hence I look forward to becoming a postdoctoral scholar after my Ph.D."

Sammi Rokey – Michael Cusanovich Galileo Circle Scholar Samantha graduated with her B.S. in chemistry from Illinois State University in 2020. She is currently a 4th year PhD candidate in Dr. Christopher Hulme's group. Her research specifically focuses on designing and synthesizing novel small molecule kinase inhibitors toward glioblastoma and colorectal cancer.

Annika Silverberg "Hi! My name is Annika Silverberg, I'm a second-year graduate student in Dr. Marty's lab. I study protein-lipid interactions by developing new mass spectrometry techniques. Specifically, I'm interested in how cholesterol impacts the function of serotonin receptors. I'm hoping to go into industry after getting my PhD so I can continue developing mass spectrometry methods. In my free time, I love to read, listen to music, and relax by the pool!"

Helena Woroniecka "As a fourth-year PhD candidate in the Charest lab, my research focuses on understanding cell signaling involved in chemotaxis in the overall context of cancer metastasis. The ultimate goal of my work is to aid in the development of chemotactic therapeutics targeting metastatic cancer cells. Post-graduation, I aim to pursue a career in science communication, driven by a broad need to bridge the gap between scientific innovation and societal understanding.

In an era marked by the spread of scientific misinformation, particularly evident during the pandemic and climate crisis, the need for accurate information dissemination is more urgent than ever. By translating complex scientific concepts into accessible language and engaging narratives, I aim to promote health literacy, foster informed decision-making, and facilitate the translation of scientific advancements into tangible societal benefits."