Dynamical Quantum Phase Transitions

Speaker: 
Anatoli Polkovnikov (Boston U.)
Event Date and Time: 
Thu, 2018-01-11 16:00 - 17:00
Location: 
Henning 201
Intended Audience: 
Undergraduate

Phase transitions are usually defined through emergence of singularities of free
energy of the system with changing some external parameter like temperature.
Familiar examples include liquid-gas transitions, or transitions between
paramagnetic and ferromagnetic phases. Quantum phase transitions are very similar
except that they occur at zero temperature and are driven by quantum fluctuations.
In this talk I will introduce a concept of dynamical quantum phase transitions,
where the role of parameter driving the system between different phases is played by
the evolution time following some dynamical process like a quench. Mathematically
these transitions can be understood through singularities of the Loschmidt type
return amplitude, which serves as a natural real time generalization of the
partition function. Physically these transitions are related to the singularities in
the work distribution function. These transitions are naturally explained though the
language of zeros of the return amplitude in the complex time plane, which are
similar to Fisher zeros of the partition function in the complex temperature plane
in equilibrium systems.

 
Website development by Checkmark Media. Designed by Armada.

a place of mind, The University of British Columbia

Faculty of Science
Department of Physics and Astronomy
6224 Agricultural Road
Vancouver, BC V6T 1Z1
Tel 604.822.3853
Fax 604.822.5324

Emergency Procedures | Accessibility | Contact UBC | © Copyright The University of British Columbia