Comparative Study of Forward and Diffusely Scattered Light in a Coherently Prepared Ultracold Rubidium Gas

Olave Gonzalez

Published Oct 21, 2019• 0 citations

Abstract

A comparison between forward and diffusely scattered light propagating in a coherently prepared ultracold 87Rb atomic vapor is presented. This research is part of the ongoing effort to characterize the processes, such as diffusion, that contribute to coherence loss in atomic media under conditions of electromagnetically induced transparency, for applications in realistic systems. Toward this end, a magneto optical trap (MOT) of 87Rb has been built, and the atomic vapor sample characterized in terms of atomic density, shape and size, temperature, and optical depth. Next, two co-propagating beams were sent through the sample, to establish an electromagnetically induced transparency in a Λ-type system. In these measurements the two laser fields are not phase-locked, so ground state coherence will be affected by the lasers' phase fluctuations. Observation of the forward and diffusely scattered light were made for different conditions of probe pulse length, control field intensity, and probe field frequency detuning. Storage and retrieval of slow light pulses was achieved for the forward scattering (transmission) channel, but was not observed unambiguously in the diffusely scattered (fluorescence) channel.

DOI: 10.25777/309d-2g02

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