Physics World

Laser cooling the atom of atoms

Dieter Meschede

Published Jun 1, 1993• 0 citations

Abstract

Experiments with atomic hydrogen are widespread because hydrogen is the simplest and theoretically most accessible atom. This is not only true for isolated atoms, but also for spin-polarised gases of cold hydrogen. In this unique system, in which the total spins of all the hydrogens are parallel, the atoms only interact in one of the large number of possible molecular potentials. This potential (Known as 3 Σ) does not allow bound states, leading to the expectation that spin-polarised hydrogen remains gaseous down to zero kelvin. But the lack of a suitable laser source for cooling hydrogen has prevented experimenters investigating the wealth of new physics expected at these temperatures.

DOI: 10.1088/2058-7058/6/6/19

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