condensed matter physics

Radzihovsky

kdcadmin — Thu, 23 Mar 2023 18:21:14 +0000

Leo Radzihovsky

Affiliations

Fellow of CTQM
Professor, Department of Physics, University of Colorado Boulder

Bio

My research interests are:

Degenerate Atomic Gases
Liquid Crystals and Other 'Soft' Condensed Matter
Disordered Systems
Nonequilibrium Phenomena
Quantum Hall Effect
Superconductivity

For more details, please see my Physics Department homepage.

CTQM Role

CTQM Fellow

Research Category

condensed matter physics

radzihov@colorado.edu

Phone

303-492-5436 (office)

303-492-2998 (fax)

Website

http://spot.colorado.edu/~radzihov/

Nandkishore

kdcadmin — Thu, 23 Mar 2023 17:51:06 +0000

Rahul Nandkishore

Affiliations

Fellow of CTQM
Director of CTQM
Associate Professor, Department of Physics, University of Colorado Boulder

Bio

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.

Selected Publications

1. Non-local Adiabatic Response of a Localized System to Local Manipulations, V. Khemani, R. Nandkishore and S.L. Sondhi, Nature Physics 11, 560-565 (2015)

2. Rare region effects dominate weakly disordered 3D Dirac points, R. Nandkishore, D.A. Huse and S.L. Sondhi, Phys. Rev. B 89, 245110 (2014)

3. Localization Protected Quantum Order, D.A. Huse, R. Nandkishore, A. Pal, V. Oganesyan and S.L. Sondhi, Phys. Rev. B 88, 014206 (2013)

3. Chiral superconductivity from repulsive interactions in doped graphene. R. Nandkishore, L.S. Levitov and A.V. Chubukov, Nature Physics. 8, 158-163 (2012)

CTQM Role

CTQM Fellow

Research Category

condensed matter physics

Rahul.Nandkishore@Colorado.EDU

Phone

303-492-5404

Website

https://sites.google.com/a/colorado.edu/rahul-nandkishore-webpage/

Lucas

kdcadmin — Thu, 23 Mar 2023 17:47:59 +0000

Andrew Lucas

Affiliations

Fellow of CTQM
Associate Professor, Department of Physics, University of Colorado Boulder

Bio

I have worked on a variety of topics at the interface of condensed matter, high energy and mathematical physics. Recent interests include: bounds and constraints on transport and quantum information scrambling, the emergence of hydrodynamics in closed quantum systems (especially fluids of electrons in metals), and the AdS/CFT correspondence.

CTQM Role

CTQM Fellow

Research Category

condensed matter physics

high energy physics

Andrew.J.Lucas@Colorado.EDU

Website

https://sites.google.com/colorado.edu/andrew-lucas/

Gurarie

kdcadmin — Wed, 15 Mar 2023 17:30:06 +0000

Victor Gurarie

Affiliations

Fellow of CTQM
Professor, Department of Physics, University of Colorado Boulder

Bio

I am interested in emergent phenomena in condensed matter and many body physics, when the behavior of many-body systems cannot be reduced to a sum of their constituent parts. Common methods used in my work are the nonperturbative techniques of many-body theory and quantum field theory. My work has applications within the new field of the ultracold atomic gases, in the more conventional condensed matter physics, as well as to the mathematical aspects of quantum field theory.

CTQM Role

CTQM Fellow

Research Category

condensed matter physics

victor.gurarie@colorado.edu

Phone

303-735-5898 (office)

Hermele

kdcadmin — Tue, 14 Mar 2023 19:43:34 +0000

Michael Hermele

Affiliations

Fellow of CTQM
Waldo E. Rennie Professor of Theoretical Physics, Department of Physics, University of Colorado Boulder

Bio

Michael Hermele is a theoretical physicist interested in quantum phases of matter, strongly correlated systems, and other aspects and areas of quantum many-body systems. His background is in condensed matter physics, and much of his recent work also draws on ideas from quantum information science, high-energy physics, and mathematical physics. More specific current interests include topological and fracton phases of matter, and solid state materials with strong spin-orbit coupling and substantial electron interactions. He is the Deputy Director of the Simons Collaboration on Ultra-Quantum Matter.

CTQM Role

CTQM Fellow

Research Category

condensed matter physics

mathematical physics

michael.hermele@colorado.edu

Phone

303-492-7466 (office)

303-492-3352 (fax)

Website

http://spot.colorado.edu/~hermele

Condensed Matter Physics

kdcadmin — Thu, 09 Mar 2023 21:42:11 +0000

Condensed Matter Physics kdcadmin Thu, 03/09/2023 - 2:42 pm

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.

CTQM Fellow(s)

Law and Disorder

kdcadmin — Mon, 06 Apr 2015 17:41:24 +0000

Law and Disorder kdcadmin Mon, 04/06/2015 - 11:41 am

As disorder increases (l–r) in Weyl semimetal, a threshold is reached where a transition occurs between a quantum phase in which electrons get more localized and stop moving and a quantum phase with less disorder in which the electrons never become localized and Weyl semimetal acts like a conductor on steroids. Remarkably, the two quantum phases can transition back and forth from one to the other.

Image Credit

The Center for Theory of Quantum Matter and Steve Burrows

In everyday life, conductors are materials that conduct electricity. These materials are used to make metallic wires that carry electricity into our homes. In contrast, insulators, which don’t conduct electricity, surround these wires in our plugs so we don’t get electrocuted plugging in our computers, appliances, and lights. The difference between a conductor and an insulator is often the amount of disorder, or impurities, present in an electronic material. If such disorder exceeds a certain threshold, the impurities can actually stop electron flow and turn a conductor into an insulator, all because of a phenomenon known as localization.

Localization traps electrons in place and prevents them from moving through a material. Showing exactly how localization works requires the complex mathematics of quantum mechanics. Since quantum mechanics leads to all sorts of wild and crazy things, CTQM Junior Fellow Sergey Syzranov and CTQM Fellows Victor Gurarie and Leo Radzihovsky decided to investigate localization in higher dimensions. The wonderful thing about being theorists is that they didn’t consider stopping at three dimensions either.

The three theorists discovered something quite interesting happens in sufficiently high dimensions: Depending on whether or not the disorder exceeds a certain threshold, all conductors will be in one of two distinct quantum phases. In the more disordered phase as the disorder increases, more and more electrons become localized and stop moving—much like they would in our ordinary three-dimensional world. Electrons in this state behave pretty much like they do in conventional conductors.

However, the second phase with less disorder has characteristics that were totally unexpected. In this phase, even when the disorder is added (although not beyond the threshold), the electrons never become localized. As a result, electronic materials in this quantum state behave like conductors on steroids. Even resistance due to impurities doesn’t stop the flow of electrons inside them.

What’s even more curious is that near the disorder threshold, the two quantum phases can transition back and forth from one to the other. Such a quantum phase transition is quite remarkable because electronic materials are complicated, and the two phases are very different.

In the process of learning more about this remarkable quantum phase transition, the theorists realized there may be a way to observe such a transition in a real material such as Weyl semimetal. Weyl semimetal is a three-dimensional analog of graphene. According to the new theory, the quantum phase transition will occur in three dimensions in this unique material, opening the door to observing it in the laboratory!

Right now, it’s impossible to predict the impact of this important discovery on the future of electronics. Theorists often open up new frontiers in science, typically without realizing what those frontiers will look like. For example, when Heinrich Hertz, discoverer of electromagnetic waves, was asked about the ramifications of his discovery, he replied, “Nothing, I guess.” Nothing has turned out to be radio, television, and cell phones, to name a few devices in widespread use today.

Principal Investigators

Leo Radzihovsky

Victor Gurarie

Research Topics

condensed matter physics