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Title: Anomalous transport from hot quasiparticles in interacting spin chains
Abstract Many experimentally relevant quantum spin chains are approximately integrable, and support long-lived quasiparticle excitations. A canonical example of integrable model of quantum magnetism is the XXZ spin chain, for which energy spreads ballistically, but, surprisingly, spin transport can be diffusive or superdiffusive. We review the transport properties of this model using an intuitive quasiparticle picture that relies on the recently introduced framework of generalized hydrodynamics. We discuss how anomalous linear response properties emerge from hierarchies of quasiparticles both in integrable and near-integrable limits, with an emphasis on the role of hydrodynamic fluctuations. We also comment on recent developments including non-linear response, full-counting statistics and far-from-equilibrium transport. We provide an overview of recent numerical and experimental results on transport in XXZ spin chains.  more » « less
Award ID(s):
2236517 1653271
PAR ID:
10487967
Author(s) / Creator(s):
;
Publisher / Repository:
Institute of Physics
Date Published:
Journal Name:
Reports on Progress in Physics
Volume:
86
Issue:
3
ISSN:
0034-4885
Page Range / eLocation ID:
036502
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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