Dynamical density wave order in an atom–cavity system. (8th February 2021)

• Record Type: Journal Article
• Authors: Georges, Christoph; Cosme, Jayson G; Keßler, Hans; Mathey, Ludwig; Hemmerich, Andreas
• Is Part Of: New journal of physics. Volume 23:Number 2(2021)
• Publication Date: 2021-02-08
• Subjects: quantum gases -- cavity QED -- optomechanics -- non-equilibrium dynamics; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/abdf9c
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: We theoretically and experimentally explore the emergence of a dynamical density wave (DW) order in a driven dissipative atom–cavity system. A Bose–Einstein condensate is placed inside a high finesse optical resonator and pumped sideways by an optical standing wave. The pump strength is chosen to induce a stationary superradiant checkerboard DW order of the atoms stabilized by a strong intracavity light field. We show theoretically that, when the pump is modulated with sufficient strength at a frequency ω d close to a systemic resonance frequency ω >, a dynamical DW order emerges, which oscillates at the two frequencies ω > and ω < = ω d − ω > . This order is associated with a characteristic momentum spectrum, also found in experiments in addition to remnants of the oscillatory dynamics presumably damped by on-site interaction and heating, not included in the calculations. The oscillating density grating, associated with this order, suppresses pump-induced light scattering into the cavity. Similar mechanisms might be conceivable in light-driven electronic matter.