Uncovering the nonequilibrium phase structure of an open quantum spin system

• Verfasst von: Helmrich, Stephan [VerfasserIn]
• Verfasst von: Arias Suárez, Alda Lisseth [VerfasserIn]
• Verfasst von: Whitlock, Shannon [VerfasserIn]
• Titel: Uncovering the nonequilibrium phase structure of an open quantum spin system
• Verf.angabe: S. Helmrich, A. Arias, and S. Whitlock
• E-Jahr: 2018
• Jahr: 6 August 2018
• Umfang: 11 S.
• Fussnoten: Published 6 August 2018 ; Gesehen am 02.10.2019
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2018
• Band/Heft Quelle: 98(2018,2) Artikel-Nummer 022109, 11 Seiten
• ISSN Quelle: 2469-9934
• DOI: doi:10.1103/PhysRevA.98.022109
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1678033103

Abstract

We experimentally and theoretically investigate the nonequilibrium phase structure of a well-controlled driven-dissipative quantum spin system governed by the interplay of coherent driving, spontaneous decay, and long-range spin-spin interactions. We discover that the rate of population loss provides a convenient macroscopic observable that exhibits power-law scaling with the driving strength over several orders of magnitude. The measured scaling exponents reflect the underlying nonequilibrium phase structure of the many-body system, which includes dissipation-dominated, paramagnetic, and critical regimes as well as an instability which drives the system towards states with high excitation density. This opens up a means to study and classify quantum systems out of equilibrium and extends the domain where scale-invariant behavior may be found in nature.