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Physical Review A

Suppression of Zeeman relaxation in cold collisions of P21/2 atoms

Timur V. Tscherbul, Alexei A. Buchachenko, A. Dalgarno, M. Lu, Jonathan D. Weinstein

Published Oct 1, 2009• 15 citations
Publisher

Abstract

We present a combined experimental and theoretical study of angular momentum depolarization in cold collisions of $^{2}P$ atoms in the presence of an external magnetic field. We show that collision-induced Zeeman relaxation of $\text{Ga}({^{2}P}_{1/2})$ and $\text{In}({^{2}P}_{1/2})$ atoms in cold $^{4}\text{H}\text{e}$ gas is dramatically suppressed compared to atoms in ${^{2}P}_{3/2}$ states. Using rigorous quantum-scattering calculations based on ab initio interaction potentials, we demonstrate that Zeeman transitions in collisions of atoms in ${^{2}P}_{1/2}$ electronic states occur via couplings to the ${^{2}P}_{3/2}$ state induced by the anisotropy of the interaction potential. Our results suggest the feasibility of sympathetic cooling and magnetic trapping of ${^{2}P}_{1/2}$-state atoms, such as halogens, thereby opening up exciting areas of research in precision spectroscopy and cold-controlled chemistry.

DOI
10.1103/physreva.80.040701

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