Emergent eigenstate solution to quantum dynamics far from equilibrium

Lev Vidmar, Deepak Iyer, Marcos Rigol

Research output: Contribution to journalReview article

33 Scopus citations

Abstract

The quantum dynamics of interacting many-body systems has become a unique venue for the realization of novel states of matter. Here, we unveil a new class of nonequilibrium states that are eigenstates of an emergent local Hamiltonian. The latter is explicitly time dependent and, even though it does not commute with the physical Hamiltonian, it behaves as a conserved quantity of the time-evolving system. We discuss two examples of integrable systems in which the emergent eigenstate solution can be applied for an extensive (in system size) time: transport in one-dimensional lattices with initial particle (or spin) imbalance and sudden expansion of quantum gases in optical lattices. We focus on noninteracting spinless fermions, hard-core bosons, and the Heisenberg model.We show that current-carrying states can be ground states of emergent local Hamiltonians, and that they can exhibit a quasimomentum distribution function that is peaked at nonzero (and tunable) quasimomentum. We also show that time-evolving states can be highly excited eigenstates of emergent local Hamiltonians, with an entanglement entropy that does not exhibit volume-law scaling.

Original languageEnglish (US)
Article number021012
JournalPhysical Review X
Volume7
Issue number2
DOIs
StatePublished - Apr 25 2017

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Emergent eigenstate solution to quantum dynamics far from equilibrium'. Together they form a unique fingerprint.

  • Cite this