Detecting and characterising dynamical quantum phase transitions through higher moments

Ian McCulloch (U of Queensland, Brisbane)

Sep 12. 2022, 15:45 — 16:30

One conception of a dynamical quantum phase transition (DQPT) is the appearance of non-analyticies in the return rate (Loschmidt Echo), which is the overlap of an initial state at t=0 with a time-evolved state at time t with respect to a global quench.  I will present an algorithm for calculating the moments of the return rate for translationally invariant infinite MPS, which is expressed in terms of the spectrum of the mixed transfer matrix.  This leads naturally to analogues of Fisher and Lee-Yang zeros for the return rate and a topological interpretation/classification of DQPT's.

Further Information
ESI Boltzmann Lecture Hall
Associated Event:
Tensor Networks: Mathematical Structures and Novel Algorithms (Thematic Programme)
Frank Pollmann (TU Munich)
Norbert Schuch (U of Vienna)
Frank Verstraete (Ghent U)