Temperature alone can tune atomic scattering resonances in cold gases

In ultracold mixtures, scattering resonances normally arise by accident or require careful magnetic tuning. By extending Casimir-like fermion-mediated interactions to finite temperature, the authors show that thermal smearing of the Fermi surface reshapes the effective potential between impurity atoms, shifting the resonance position continuously with temperature. The resonance location moves predictably as temperature changes, offering a clean experimental signature. Recent loss-feature measurements in Bose-Fermi mixtures match this temperature-controlled resonance picture, suggesting the mechanism is already at work in existing experiments.