Characterizing the temperature dependence of Fano-Feshbach resonances of Ultracold Polarized Thulium

TL;DR

This study investigates how temperature affects Fano-Feshbach resonances in ultracold thulium atoms, revealing the dominant role of Stark shifts and providing detailed resonance parameters through experimental and theoretical analysis.

Contribution

It offers a detailed analysis of temperature-dependent shifts of Fano-Feshbach resonances in thulium, combining experimental data with a 3-body recombination theory to extract resonance parameters.

Findings

Temperature shifts are consistent with 3-body recombination theory.

Stark effect is the dominant contributor to overall resonance shifts.

Resonance parameters, including magnetic moments, are successfully extracted.

Abstract

Recent studies demonstrated anomalous temperature shifts for some Fano-Feshbach resonances of thulium atoms. These anomalies were explained by the variation in light intensity in the optical dipole trap, which accompanied changes in temperature. In addition, a temperature-related transformation of the statistics of the interresonance spacing was demonstrated [1]. Here, we analyze the shifts of isolated s- and d-type Fano-Feshbach resonances of ultracold thulium atoms with temperature for a fixed depth of an optical dipole trap. The measurements are consistent with the 3-body recombination-based theory of the temperature-related resonance shift and enable the extraction of the resonance parameters, particularly the magnetic moments of closed channel states. This parameter and the known polarizability of the open channel enable us to separate the contributions of the temperature and Stark shift to the overall shift of the resonances and show the dominant role of the Stark effect in the overall shift.