Condensed Matter

Condensed matter physics is the branch of physics that studies systems of very large numbers of particles in a condensed state, like solids or liquids. Condensed matter physics wants to answer questions like: why is a material magnetic? Or why is it insulating or conducting? Or new, exciting questions like: what materials are good to make a reliable quantum computer? Can we describe gravity as the behavior of a material? The behavior of a system with many particles is very different from that of its individual particles. We say that the laws of many body physics are emergent or collective. Emergence explains the beauty of physics laws.

Displaying 1237 - 1242 of 1242

Orthogonality catastrophe 40 years later: fidelity approach, criticality and boundary CFT

Lorenzo Campos Venuti ISI, Turin
December 10, 2010

PIRSA:10120023
Condensed Matter
1-loop diagram in AdS space and the random disorder problem

Yanwen Shang Citigroup Incorporated
November 26, 2010

PIRSA:10110079
Condensed Matter
Holographic Branching and Entanglement Renormalization

Glen Evenbly Georgia Institute of Technology
November 19, 2010

PIRSA:10110076
Condensed Matter
Torsion as a Probe in Condensed Matter Systems

Taylor Hughes University of Illinois Urbana-Champaign
November 12, 2010

PIRSA:10110065
Condensed Matter
Mutual information and the structure of entanglement in quantum field theory

Brian Swingle Brandeis University
October 26, 2010

PIRSA:10100087
Condensed Matter
Quantum Matter

436 talks

Collection NumberS021
Talk

Symmetry and Causality Constraints on Fermi Liquids

Umang Mehta

March 04, 2025

PIRSA:25030161

Condensed Matter

Fractional Quantum Hall states Under Decoherence

Zijian Wang Tsinghua University

February 25, 2025

PIRSA:25020047

Condensed Matter

Nonabelian Anyon Condensation in 2+1d topological orders: A String-Net Model Realization

Yidun Wan Fudan University

February 18, 2025

PIRSA:25020042

Condensed Matter

The Charge Gap exceeds the Neutral Gap in Fractional Quantum Hall Systems

Bruno Nachtergaele University of California, Davis

February 13, 2025

PIRSA:25020032

Condensed Matter

Exploring Quantum Many-Body Scars: Anomalies to Thermalization in Quantum Systems

Julia Wildeboer Brookhaven National Laboratory

February 04, 2025

PIRSA:25020030

Condensed Matter

An SPT-LSM theorem for weak SPTs with non-invertible symmetry

Sal Pace

November 19, 2024

PIRSA:24110081

Condensed Matter

Microscopic Roadmap to a Yao-Lee Spin-Orbital Liquid

Hae-Young Kee University of Toronto

November 12, 2024

PIRSA:24110069

Condensed Matter

Exotic superconductivity in UTe2

Sheng Ran

November 05, 2024

PIRSA:24100142

Condensed Matter
See all from this collection

Orthogonality catastrophe 40 years later: fidelity approach, criticality and boundary CFT

Lorenzo Campos Venuti ISI, Turin
December 10, 2010

PIRSA:10120023
Condensed Matter
More than forty years ago Nobel laureate P.W. Anderson studied the overlap between two nearby ground states. The result that the overlap tends to zero in the thermodynamics limit was catastrophic for those times. More recently the study of the overlap between ground states, i.e. the fidelity, led to the formulation of the so called fidelity approach to (quantum) phase transition (QPT). This new approach to QPT does not rely on the identification of order parameters or symmetry pattern; rathers it embodies the theory of phase transitions with an operational meaning in terms of measurements. Nowadays orthogonality of ground states is much less surprising. I will provide the general scaling behavior of the fidelity at regular and at critical points of the phase diagrams, Anderson's result being a particular case. These results are useful to many areas of theoretical physics. A related quantity extensively studied here, the fidelity susceptibility, is well known in various other contexts under different names. In metrology it is called quantum Fisher information; in the theory of adiabatic computation it represents the figure of merit for efficient computation; in yet another context it is known as (real part of) the Berry geometric tensor.
1-loop diagram in AdS space and the random disorder problem

Yanwen Shang Citigroup Incorporated
November 26, 2010

PIRSA:10110079
Condensed Matter
AdS/CFT has proven itself a powerful tool in extending our understanding of strongly coupled quantum theories. While studies of AdS/CFT have predominantly focused on tree level calculations, there has been growing interest in the loop effect recently. We studied the 1-loop correction to the gauge boundary-to-boundary correlator due to its coupling to a complex scalar field. In this talk, I would outline our main results, explain the Cutkosky rule in AdS space, and discuss an extra divergence we found in both real and imaginary part of the loop integral. I would then combine our analysis with the replica trick to demonstrate a possible application where one attempts to calculate the DC conductivity in a condensed matter system with random disorder and discuss the limitation and difficulties of our method in its current form.
Holographic Branching and Entanglement Renormalization

Glen Evenbly Georgia Institute of Technology
November 19, 2010

PIRSA:10110076
Condensed Matter
Entanglement renormalization is a coarse-graining transformation for quantum lattice systems. It produces the multi-scale entanglement renormalization ansatz, a tensor network state used to represent ground states of strongly correlated systems in one and two spatial dimensions. In 1D, the MERA is known to reproduce the logarithmic violation of the boundary law for entanglement entropy, S(L)~log L, characteristic of critical ground states. In contrast, in 2D the MERA strictly obeys the entropic boundary law, S(L)~L, characteristic of gapped systems and a class of critical systems. Therefore a number of highly entangled 2D systems, such as free fermions with a 1D Fermi surface, Fermi liquids and spin Bose metals, which display a logarithmic violation of the boundary law, S(L)~L log L, cannot be described by a regular 2D MERA. It is well-known that at low energies, a many-body system may decouple into two or more independent degrees of freedom (e.g. spin-charge separation in 1D systems of electrons). In this talk I will explain how, in systems where low energy decoupling occurs, entanglement renormalization can be used to obtain an explicit decoupled description. The resulting tensor network state, the branching MERA, can reproduce a logarithmic violation of the boundary law in 2D and, as additional numeric evidence also suggests, might be a good ansatz for the highly entangled systems with a 1D Fermi (or Bose) surface mentioned above. In addition, after recalling that the MERA can be regarded as a specific (discrete) realization of the holographic principle, we will see that the branching MERA leads to exotic holographic geometries.
Torsion as a Probe in Condensed Matter Systems

Taylor Hughes University of Illinois Urbana-Champaign
November 12, 2010

PIRSA:10110065
Condensed Matter
: In this talk I will review the common appearance of torsion in solids as well as some new developments. Torsion typically appears in condensed matter physics associated to topological defects known as dislocations. Now we are beginning to uncover new aspects of the coupling of torsion to materials. Recently, a dissipationless viscosity has been studied in the quantum Hall effect. I will connect this viscosity to a 2+1-d torsion Chern-Simons term and discuss possible thought experiments in which this could be measured. Additionally I will discuss a new topological defect in 3+1-d, the torsional monopole, which does not require a lattice deformation to exist. If present, torsional monopoles are likely to impact the behavior of materials with strong spin-orbit coupling such as topological insulators.
Mutual information and the structure of entanglement in quantum field theory

Brian Swingle Brandeis University
October 26, 2010

PIRSA:10100087
Condensed Matter
In this talk I will describe my recent work on the structure of entanglement in field theory from the point of view of mutual information. I will give some basic scaling intuition for the entanglement entropy and then describe how this intuition is better captured by the mutual information. I will also describe a proposal for twist operators that can be used to calculate the mutual information using the replica method. Finally, I will discuss the relevance of my results for holographic duality and entanglement based simulation methods for many body systems.
Quantum Matter

436 talks

Collection NumberS021
Talk

Symmetry and Causality Constraints on Fermi Liquids

Umang Mehta

March 04, 2025

PIRSA:25030161

Condensed Matter

Fractional Quantum Hall states Under Decoherence

Zijian Wang Tsinghua University

February 25, 2025

PIRSA:25020047

Condensed Matter

Nonabelian Anyon Condensation in 2+1d topological orders: A String-Net Model Realization

Yidun Wan Fudan University

February 18, 2025

PIRSA:25020042

Condensed Matter

The Charge Gap exceeds the Neutral Gap in Fractional Quantum Hall Systems

Bruno Nachtergaele University of California, Davis

February 13, 2025

PIRSA:25020032

Condensed Matter

Exploring Quantum Many-Body Scars: Anomalies to Thermalization in Quantum Systems

Julia Wildeboer Brookhaven National Laboratory

February 04, 2025

PIRSA:25020030

Condensed Matter

An SPT-LSM theorem for weak SPTs with non-invertible symmetry

Sal Pace

November 19, 2024

PIRSA:24110081

Condensed Matter

Microscopic Roadmap to a Yao-Lee Spin-Orbital Liquid

Hae-Young Kee University of Toronto

November 12, 2024

PIRSA:24110069

Condensed Matter

Exotic superconductivity in UTe2

Sheng Ran

November 05, 2024

PIRSA:24100142

Condensed Matter
See all from this collection

Title	Speaker(s)	Date	Talk Type	Info link
Orthogonality catastrophe 40 years later: fidelity approach, criticality and boundary CFT	Lorenzo Campos Venuti	2010-12-10	Scientific Series	View details
1-loop diagram in AdS space and the random disorder problem	Yanwen Shang	2010-11-26	Scientific Series	View details
Holographic Branching and Entanglement Renormalization	Glen Evenbly	2010-11-19	Scientific Series	View details
Torsion as a Probe in Condensed Matter Systems	Taylor Hughes	2010-11-12	Scientific Series	View details
Mutual information and the structure of entanglement in quantum field theory	Brian Swingle	2010-10-26	Scientific Series	View details
Quantum Matter				View details

Condensed Matter

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