Quantum Institute: Visitor Schedule

The Quantum Lunch is regularly held on Thursdays in the Theoretical Division Conference Room, TA-3, Building 123, Room 121.

The organizing committee includes Malcolm Boshier (P-21), Diego Dalvit (T-4), Michael Di Rosa (C-PCS), Sebastian Deffner (T-4 & CNLS), Changhyun Ryu (P-21) , Nikolai Sinitsyn (T-4), Rolando Somma (T-4), Christopher Ticknor (T-1), and Wojciech Zurek (T-4).

For more information, or to nominate a speaker, contact Sebastian Deffner.

To add your name to the Quantum Lunch email list, contact Kacy Hopwood.

Thursday June 16, 2016
12:30 PM - 2:00 PM

Speaker: Adam Kaufman (Harvard University)

Technical Host: Wojciech Zurek

TOPIC: Quantum thermalization through entanglement

Abstract
Entanglement within a many-body system is a defining feature of strongly correlated quantum systems. Recent theoretical developments point to the entropy of entanglement as a means to classify unusual quantum phases, such as spin liquids and topological phases. In this talk I will present an experimental scheme to probe entanglement in itinerant systems through interference of two copies of a many-body state. Akin to Hong-Ou-Mandel interference of photons, this measurement performed with ultracold atoms probes the indistinguishability of quantum states. I will discuss how this interference allows us to measure quantum purity, second order Renyi (entanglement) entropy and mutual information within finite Bose-Hubbard chains. In the context of these techniques, I will focus on our investigation of the dynamics of quenched, isolated bosonic systems. Here we observe that thermal ensembles appear to emerge from a pure quantum state, while the entanglement entropy quantitatively approaches the thermal entropy. Our observations experimentally illustrate the role of entanglement in facilitating thermalization of pure systems undergoing unitary dynamics.

Adam Kaufman received his undergraduate degree at Amherst College, and recently received his Ph.D. in physics at JILA and the University of Colorado at Boulder. His Ph.D. work focused on quantum control of single atoms in optical tweezers using laser-cooling techniques. He is now a post-doctoral fellow at Harvard University, in the group of Markus Greiner, where he works on microscopy of strongly-interacting systems of lattice-confined bosons.