title: Closed and open system dynamics in a fermionic chain with a microscopically specified bath: relaxation and thermalization.
abstract: We study thermalization in a one-dimensional quantum system consisting of a noninteracting fermionic chain with each site of the chain coupled to an additional bath site. Using a density matrix renormalization group algorithm we investigate the time evolution of the observables in the chain after a quantum quench. For low densities we show that the intermediate time dynamics can be quantitatively described by a system of coupled equations of motion. For higher densities our numerical results show a prethermalization for the local observables at intermediate times and a full thermalization to the grand canonical ensemble at long times. For the case of a weak bath-chain coupling we find, in particular, a Fermi momentum distribution in the chain in equilibrium in spite of the seemingly oversimplified bath in our model.
authors.affiliation: Department of Physics and Research Center OPTIMAS, Technical University Kaiserslautern, D-67663 Kaiserslautern, Germany.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Sedlmayr
authors.forename: Jie
authors.initials: J
authors.lastname: Ren
authors.forename: Florian
authors.initials: F
authors.lastname: Gebhard
authors.forename: Jesko
authors.initials: J
authors.lastname: Sirker