Collisional and molecular spectroscopy in an ultracold Bose-Bose mixture

TL;DR

This paper reports spectroscopic measurements and the observation of Feshbach resonances in a Bose-Bose mixture, advancing the understanding needed to create dipolar molecular Bose-Einstein condensates.

Contribution

It provides new spectroscopic data and improved collisional models for 41K87Rb, aiding the formation of dipolar molecules in ultracold gases.

Findings

Identification of two weakly bound molecular levels

Observation of narrow d-wave Feshbach resonances

Enhanced collisional model accuracy for 41K87Rb

Abstract

The route toward a Bose-Einstein condensate of dipolar molecules requires the ability to efficiently associate dimers of different chemical species and transfer them to the stable rovibrational ground state. Here, we report on recent spectroscopic measurements of two weakly bound molecular levels and newly observed narrow d-wave Feshbach resonances. The data are used to improve the collisional model for the Bose-Bose mixture 41K87Rb, among the most promising candidates to create a molecular dipolar BEC.