Bose-Einstein condensation of chromium

TL;DR

This paper reports the creation of a Bose-Einstein condensate of chromium atoms, enabling studies of anisotropic long-range interactions in quantum gases, achieved through specialized cooling and trapping techniques.

Contribution

It demonstrates the first realization of chromium Bose-Einstein condensation, highlighting novel cooling strategies tailored to its unique electronic and magnetic properties.

Findings

Condensate observed at T~700nK with over 50,000 atoms.

Inversion of aspect ratio during expansion indicates anisotropic interactions.

Critical behavior of condensate fraction as a function of temperature.

Abstract

We report on the generation of a Bose-Einstein condensate in a gas of chromium atoms, which will make studies of the effects of anisotropic long-range interactions in degenerate quantum gases possible. The preparation of the chromium condensate requires novel cooling strategies that are adapted to its special electronic and magnetic properties. The final step to reach quantum degeneracy is forced evaporative cooling of 52Cr atoms within a crossed optical dipole trap. At a critical temperature of T~700nK, we observe Bose-Einstein condensation by the appearance of a two-component velocity distribution. Released from an anisotropic trap, the condensate expands with an inversion of the aspect ratio. We observe critical behavior of the condensate fraction as a function of temperature and more than 50,000 condensed 52Cr atoms.