Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Home 
 People 
 Current 
 Executive Committee 
 Postdocs 
 Visitors 
 Students 
 Research 
 Publications 
 Conferences 
 Workshops 
 Sponsorship 
 Talks 
 Seminars 
 Postdoc Seminars Archive 
 Quantum Lunch 
 Quantum Lunch Archive 
 P/T Colloquia 
 Archive 
 Ulam Scholar 
 
 Postdoc Nominations 
 Student Requests 
 Student Program 
 Visitor Requests 
 Description 
 Past Visitors 
 Services 
 General 
 
 History of CNLS 
 
 Maps, Directions 
 CNLS Office 
 T-Division 
 LANL 
 
Tuesday, March 21, 2017
2:00 PM - 3:00 PM
CNLS Conference Room (TA-3, Bldg 1690)

Colloquium

Quantum Time Crystal By Decoherence in Ring Crystals

KEIJI NAKATSUGAWA
Hokkaido University

A quantum time crystal (QTC) is a novel quantum mechanical ground state which spontaneously breaks time-translation symmetry: Time-translation symmetry of a system with thermodynamic (infinite volume) limit is expected to become discrete by spontaneous breaking of time-translation symmetry, but the possibility to realize such system is still under debate. Meanwhile, Volovik proposes the possibility of an effective QTC, that is, a QTC with a finite size in time. In this presentation we show that time-translation symmetry of a finite-size system becomes discrete by a transition caused by decoherence, which is best described using an incommensurate charge density wave (ICDW). We use a ring-shaped ICDW threaded by a fluctuating magnetic flux to model an effective QTC with a finite size in space and time: time-translation symmetry becomes discrete by measuring the ground state of an ICDW ring and the lifetime of the QTC is extended using decoherence.

Host: Avadh Saxena