Dissipative Distillation of Supercritical Quantum Gases

Abstract

We experimentally realize a method to produce non-equilibrium Bose Einstein condensates with condensed fraction exceeding those of equilibrium samples with the same parameters. To do this, we immerse an ultracold Bose gas of 87Rb in a cloud of 39K with substantially higher temperatures, providing a controlled source of dissipation. By combining the action of the dissipative environment with evaporative cooling, we are able to progressively distil the non-equilibrium Bose-Einstein condensate from the thermal cloud. We show that by increasing the strength of the dissipation it is even possible to produce condensates above the critical temperature. We finally demonstrate that our out-of-equilibrium samples are long-lived and do not reach equilibrium in a time that is accessible for our experiment. Due to its high degree of control, our distillation process is a promising tool for the engineering of open quantum systems.

References in corpus (8)

• Quantum fluids of light
• An Open-System Quantum Simulator with Trapped Ions
• Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose condensate
• Non-equilibrium coherence dynamics in one-dimensional Bose gases
• Ultracold atoms out of equilibrium
• Effects of Interactions on the Critical Temperature of a Trapped Bose Gas
• Accurate near-threshold model for ultracold KRb dimers from interisotope Feshbach spectroscopy
• Can a Bose gas be saturated?