Events Archive

Pseudo-Gauge Field in Dirac/Weyl Materials/ Chaoxing Liu/ Pennsylvania State University
Tue, Nov 9, 2021, 12:30 pm12:30 pm

 

In solid materials, electrons are usually described by the non-relativistic Schrodinger equation since electron velocity is much slower than the speed of light. However, the relativistic Dirac/Weyl equation can emerge as a low-energy effective theory for electrons in certain materials. These systems are…

CM/AMO Seminar/Spin dynamics of ultracold atoms in optical lattices/Wolfgang Ketterle, MIT
Tue, Oct 26, 2021, 12:30 pm12:30 pm

Ultracold atoms offer a unique platform to perform quantum simulations of quantum materials and many-body systems.  When atoms with spin are arranged in an optical lattice in form of a Mott insulator, they realize paradigmatic Heisenberg spin models, where only neighboring spins interact.  Until very recently, all experimental studies with cold…

Condensed Matter Seminar/Toward Practical Quantum Advantage: Many-body Physics in the NISQ Era - Xiao Mi, Research Scientist, Google
Tue, Oct 5, 2021, 12:30 pm12:30 pm

 

 

    Quantum processors of today are already capable of surpassing classical supercomputers on certain specialized tasks [1]. A current milestone for the quantum information science community is the fulfilment of…

Condensed Matter Seminar - TBD
Tue, Sep 28, 2021, 12:30 pm12:30 pm
Condensed Matter Seminar - "Interplay of correlations and topology in the narrow bands of twisted bilayer graphene" Oskar Vafek, Florida State University
Tue, Sep 21, 2021, 12:30 pm12:30 pm

I will present an overview of the current theoretical understanding of the remarkable phenomenology of the twisted bilayer graphene (TBG) near the magic angle.  This includes the early insights obtained using the 2D exponentially localized Wannier basis[1] which revealed a qualitative difference between the effect of the…

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Special Condensed Matter Seminar - Yichen Huang, MIT, "Entanglement dynamics from random product states at long times"
Wed, Jun 16, 2021, 2:00 pm2:00 pm

We study the entanglement dynamics of quantum many-body systems at long times.

For upper bounds, we prove the following: (I) For any geometrically local Hamiltonian on a lattice, starting from a random product state the entanglement entropy almost never approaches the Page curve. (II) In a spin-glass model with random all-to-all…

Speaker
Condensed Matter Zoom Seminar | Srinivas Raghu, Stanford | "Lattice constructions of a web of dualities in 3 spacetime dimensions"
Wed, May 26, 2021, 2:00 pm2:00 pm

Duality transformations have played a major role in our modern understanding of quantum phenomena.  In 3 spacetime dimensions, familiar examples of duality transformations include 1) Goldstone modes of the XY model being dual to a photon, and 2) dualities involving statistical transmutation.  It has become clear recently that both of these…

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Condensed Matter Zoom Seminar | Andrea Young, UCSB | "Orbital magnetism in graphene heterostructures"
Wed, May 19, 2021, 2:00 pm2:00 pm

I will describe experiments probing magnetic states based on the spontaneous alignment of electron orbitals. Such orbital ferromagnetism may be a generic phenomena, but has, to date, found its fullest expression in graphene heterostructures in which the two dimensional orbits of electrons in distinct momentum space valleys provide the…

Speaker
Condensed Matter Zoom Seminar | Siddharth Parameswaran | "Topology and broken symmetry of excitons in two-dimensional materials"
Wed, Apr 28, 2021, 2:00 pm2:00 pm

I will discuss recent  theoretical work on exciton physics in two-dimensional materials. First, I will focus on the neutral particle-hole pair excitations of correlated “orbital Chern insulators” recently detected in twisted bilayer graphene, whose approximately flat conduction and valence bands have equal and opposite non-zero Chern number…

Speaker
Condensed Matter Zoom Seminar | Ana Maria Rey, U Colorado | "Advances in Quantum Simulation with Planar Ion Crystals"
Wed, Apr 21, 2021, 2:00 pm2:00 pm

 In this seminar I will discuss recent progress on the use of planar crystals with hundreds of ions as a platform for quantum simulation of spin and spin-boson models. The key idea is the use of a pair of lasers to couple two internal levels of the ions, that act as a spin½ degree of freedom, to the…

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Condensed Matter Zoom Seminar | Claudio Chamon, Boston U. | "TBA"
Wed, Apr 14, 2021, 2:00 pm2:00 pm

TBA

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Condensed Matter Zoom Seminar | Charles Kane, U Penn.| "Translation symmetry enriched topological phases"
Wed, Apr 7, 2021, 2:00 pm2:00 pm

The interplay between symmetry and topology allows a rich variety of electronic phases.  For layered systems, symmetry under translation by one layer protects the 3D weak topological insulator, which can be viewed as a stack of 2D topological insulators and the 2D 'weak topological superconductor', which is a stack of 1D topological…

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Condensed Matter Zoom Seminar | Eugene Demler, Harvard | "A new perspective on magnetic polarons from cold atoms"
Wed, Mar 31, 2021, 2:00 pm2:00 pm

What can we learn about a many-body system when we measure every constituent particle? Current experiments with ultracold atoms provide snapshots of many-body states with single particle resolution. I will present a recent application of this method to study magnetic polarons in antiferromagnetic Mott insulators. In…

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