Spreading of correlations in Hermitian and non-Hermitian quantum systems
Despres Julien (LPTMS – Collège de France)
During this presentation, I will give you an overview of one part of my research work done during my PhD and my postdoc concerning the spreading of correlations in isolated quantum systems governed by a Hermitian or a non-Hermitian Hamiltonian. For the Hermitian case, I will introduce a generic form of the equal-time correlation function found using a quasiparticle picture which is valid for a large number of quantum systems. From the latter, I will extract the scaling laws of the correlation edge also called Lieb-Robinson bound depending if short-range or long-range interactions are considered. For the non-Hermitian case, I will present several results concerning the spreading of correlations for the non-Hermitian short-range Ising model.