Temperature-Controlled Resonance in a Heteronuclear Quantum Gas Mixture

TL;DR

This paper introduces a novel mechanism for achieving a tunable single-channel resonance in heteronuclear quantum gases by controlling temperature, which affects the effective interaction via thermal smearing of the Fermi surface.

Contribution

It demonstrates how temperature can be used as an accessible control parameter to systematically tune resonances in ultracold quantum gases through a modified Casimir-like interaction.

Findings

Resonance position shifts systematically with temperature.

Thermal smearing reshapes the effective potential between impurities.

Experimental loss features are consistent with the temperature-controlled resonance mechanism.

Abstract

Single-channel resonances are fundamental processes in scattering of atoms, yet their occurrence is largely incidental and lacks systematic control. In this Letter, we propose a mechanism to realize a continuously tunable single-channel resonance by controlling the temperature of the heteronuclear mixture. By extending the Casimir-like mediated interaction to finite temperature, we demonstrate that thermal smearing of the Fermi surface reshapes the effective potential between impurities, giving rise to a temperature-controlled resonance (TCR) over a wide parameter range. As a direct consequence, the resonance position shifts systematically with temperature variation, providing a clear experimental signature of this mechanism. We further investigate the quench dynamics of a Bose gas immersed in a Fermi sea and demonstrate that the observed temperature-dependent loss features in recent experiments are consistent with the TCR mechanism. Our results establish temperature as a simple and experimentally accessible control knob for single-channel resonances in ultracold quantum gases.