Non-equilibrium steady states in quantum critical systems with Lifshitz scaling

• Published in: Journal of High Energy Physics
• Main Authors: Fernández, Daniel, Rajagopal, Aruna, Thorlacius, Larus
• Other Authors: Science Institute (UI), Raunvísindastofnun (HÍ), School of Engineering and Natural Sciences (UI), Verkfræði- og náttúruvísindasvið (HÍ), Háskóli Íslands, University of Iceland
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2019
• Subjects: Nuclear and High Energy Physics; Effective Field Theories; Space-Time Symmetries; Quantum Dissipative Systems; Kjarneðlisfræði; Skammtafræði; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/1528; https://doi.org/10.1007/JHEP12(2019)115

Publisher's version (útgefin grein). We study out-of-equilibrium energy transport in a quantum critical fluid with Lifshitz scaling symmetry following a local quench between two semi-infinite fluid reservoirs. The late time energy flow is universal and is accommodated via a steady state occupying an expanding central region between outgoing shock and rarefaction waves. We consider the admissibility and entropy conditions for the formation of such a non-equilibrium steady state for a general dynamical critical exponent z in arbitrary dimensions and solve the associated Riemann problem. The Lifshitz fluid with z = 2 can be obtained from a Galilean boost invariant field theory and the non-equilibrium steady state is identified as a boosted thermal state. A Lifshitz fluid with generic z is scale invariant but without boost symmetry and in this case the non-equilibrium steady state is genuinely non-thermal. This work was supported in part by the Icelandic Research Fund grant 195970- 051 and the University of Iceland Research Fund. Peer Reviewed