We describe experiments on the laser cooling of both helium-rubidium and argon-rubidium gas mixtures by collisional redistribution of radiation. Frequent alkali-noble gas collisions in the ultradense gas, with typically 200 bar of noble buffer gas pressure, shift a highly red detuned optical beam into resonance with a rubidium Dline transition, while spontaneous decay occurs close to the unshifted atomic resonance frequency. The technique allows for the laser cooling of macroscopic ensembles of gas atoms. The use of helium as a buffer gas leads to smaller temperature changes within the gas volume due to the high thermal conductivity of this buffer gas, as compared to the heavier argon noble gas, while the heat transfer within the cell is improved.

Date Published: 8 February 2012
PDF: 8 pages
Proc. SPIE 8275, Laser Refrigeration of Solids V, 827508 (8 February 2012); doi: 10.1117/12.905897

Published in SPIE Proceedings Vol. 8275:
Laser Refrigeration of Solids V
Richard I. Epstein; Mansoor Sheik-Bahae, Editor(s)