Cold atom ring laser

Balázs Megyeri

Published Jul 11, 2019• 0 citations

Abstract

This thesis will describe a cold atom ring laser that uses a cloud of magneto-optically trapped potassium atoms as a gain medium and a ring cavity for feedback. Some upgrades to the experiment were necessary, which include a new imaging axis in the vacuum system, a new atom source, alignment of some new optics and detectors to measure the powers and transverse intensity profiles of both counterpropagating cavity modes, and a new tapered amplifier for the magneto-optical trapping beams. The lasing threshold, gain mechanism, intensity correlations, and lasing into the two counterpropagating cavity modes were investigated. The results showed several transverse patterns at the lasing outputs, a threshold as a function of atom number, Mollow gain, a at second-order coherence above threshold, clearly distinguishable from that of fluorescence, nonreciprocity of the TEM\\(_{00}\\) transverse mode as a function of cavity length, and anticorrelated counterpropagating modes.

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