Laser Physics

Coherence of Trapped One-Dimensional (Quasi-)Condensates and Continuous Atom Lasers in Waveguides

Nick P. Proukakis

Published Dec 31, 2003• 10 citations

Abstract

We present a model for a continuous atom laser beam in a one-dimensional waveguide. The beam is formed by continuous Raman outcoupling of a trapped one-dimensional (quasi-)condensate, which is created by imposing a tightly confining transverse optical potential on a three-dimensional magnetically trapped ultracold thermal gas. The trapped (quasi-)condensate is modeled by a stochastic Langevin equation in which pumping arises naturally from the surrounding three-dimensional thermal cloud, which acts as its heat bath. When the outcoupling is turned on, such pumping leads to continuous replenishing of the (quasi-)condensate and thus to a steady-state operation for the atom laser, which is described by a nonlinear Schrodinger equation coupled to the Langevin equation for the (quasi-)condensate. This model is used to study the temporal and spatial evolution of the coherence length of the (quasi-)condensate and the atom laser over the entire system.

DOI: 10.25405/ncl.34578336

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