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The Atom Laser and Atom Optics

Vasillis E. Lembessis

Published Jun 24, 2020• 0 citations

Abstract

The transition of atoms from the disorder of the gaseous phase into the “disciplined” behavior of the condensate can be compared with the transformation of chaotic incoherent light into a laser light beam. This analogy leads directly to the definition of the atom laser: a device that produces a beam of boson atoms that have “escaped” from a trapped Bose–Einstein condensate. The operation of our well-known optical laser requires essentially three things: an optical cavity, an active medium, and a mechanism that allows light to escape from the cavity. Within the cavity, a huge number of atoms of the active medium interact with photons. The cavity consists essentially of two mirrors with very high reflectivity onto which the photons are reflected many times. Multiple reflections cause photons to interact continuously with atoms in the cavity, leading to a continuous generation of new photons by stimulated emission. The result is an increase in the number of photons, i.e., amplification of the beam traveling within the cavity. All of the photons have the same frequency and phase (i.e., they oscillate synchronously). Since one of the mirrors is not perfectly reflective, the photons manage to escape from the cavity, resulting in the well-known, monochromatic, and directional laser beam.

DOI: 10.1117/3.2563828.ch6

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