Dear Friends,
On Thursday, December 13, there will be an ITAMP topical lunch discussion.
Tea Room (P-226) @ CfA (60 Garden Street)
Time: 12:00-1:30
As always pizza will be served.
Speaker: Prof. Dima Abanin
Title: Measuring entanglement entropy of a generic many-body system
with a quantum switch
Abstract:
Entanglement entropy has become an important theoretical concept in
condensed matter physics, because it provides a unique tool for
characterizing quantum mechanical many-body phases and new kinds of
quantum order. However, the experimental measurement of entanglement
entropy in a many-body systems is widely believed to be unfeasible,
owing to the nonlocal character of this quantity. Here, we propose a
general method to measure the entanglement entropy. The method is
based on a quantum switch (a two-level system) coupled to a composite
system consisting of several copies of the original many-body system.
The state of the switch controls how different parts of the composite
system connect to each other. We show that, by studying the dynamics
of the quantum switch only, the Renyi entanglement entropy of the
many-body system can be extracted. We propose a possible design of the
quantum switch, which can be realized in cold atomic systems. Our work
provides a route towards testing the scaling of entanglement in
critical systems, as well as a method for a direct experimental
detection of topological order.
[1] Abanin, Demler, Phys. Rev. Lett. 109, 020504 (2012);
Looking forward to seeing you there,
Misha Lemeshko
--
Dr. Mikhail Lemeshko
Institute for Theoretical Atomic, Molecular, and Optical Physics (ITAMP)
Harvard-Smithsonian Center for Astrophysics MS-14
60 Garden St.
Cambridge, MA 02138
U.S.A.
mlemeshko(a)cfa.harvard.edu
http://sites.google.com/site/mishalemeshko/
Tel. +1 (617) 496-7610
Fax +1 (617) 496-7668