Paper

Dynamical density wave order in an atom-cavity system

Georges, Christoph, Mathey, Ludwig, Keßler, Hans, Cosme, Jayson G, Hemmerich, Andreas

2021

Overview

We theoretically and experimentally explore the emergence of a dynamical density wave 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 density wave 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 \\(\\omega_{d}\\) close to a systemic resonance frequency \\(\\omega_{>}\\), a dynamical density wave order emerges, which oscillates at the two frequencies \\(\\omega_{>}\\) and \\(\\omega_{<} = \\omega_{d} - \\omega_{>}\\). 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.

• Publisher: Cornell University Library, arXiv.org
• Subject: Bose-Einstein condensates / Density / Light scattering / Optical resonators / Standing waves