Filter Startseitehttps://www.uibk.ac.at/th-physik/laeuchli-lab/ALLE AKTUELLEN VERANSTALTUNGEN (=Ablaufdatum ist noch nicht erreicht)Tue, 24 Nov 2020 14:52:04 +0100webmaster@uibk.ac.at (Webmaster Universität Innsbruck)XIMS#SiebererNov. 26 at 10:15 online (Zoom): Group seminarTalk by Lukas Sieberer | Title: Entanglement Spectrum Crossings Reveal non-Hermitian Dynamical Topology | Abstract: The development of non-Hermitian topological band theory has led to observations of novel topological phenomena in effectively classical, driven and dissipative systems. However, for open quantum many-body systems, the absence of a ground state presents a challenge to define robust signatures of non-Hermitian topology. In my talk, I will show that such a signature is provided by crossings in the time evolution of the entanglement spectrum. These crossings occur in quenches from the trivial to the topological phase of a driven-dissipative Kitaev chain that is described by a Markovian quantum master equation in Lindblad form. At the topological transition, which can be crossed either by changing parameters of the Hamiltonian of the system or by increasing the strength of dissipation, the time scale at which the first entanglement spectrum crossing occurs diverges with a universal dynamical critical exponent. These numerical findings are corroborated with an exact analytical solution of the quench dynamics for a spectrally flat postquench Liouvillian. The exact solution suggests an interpretation of the topological quench dynamics as a fermion parity pump. The results I will present thus reveal signatures of non-Hermitian topology that are unique to quantum many-body systems and cannot be emulated in classical simulators of non-Hermitian wave physics. | See you online!http://www.uibk.ac.at/portlet-items#1832618