Stationary quantum statistics of a non-Markovian atom laser

TL;DR

This paper analyzes the steady-state quantum statistics of a non-Markovian atom laser model, revealing how memory effects influence linewidth, frequency shifts, and stability, with implications for future atom laser designs.

Contribution

It provides an exact solution to a non-Markovian atom laser model without the Born-Markov approximation, highlighting the impact of memory effects on lasing properties.

Findings

Linewidths and frequency shifts depend on pumping rates.

Occupation and linewidth exhibit nonlinear scaling behavior.

Memory effects significantly influence atom laser stability.

Abstract

We present a steady state analysis of a quantum-mechanical model of an atom laser. A single-mode atomic trap coupled to a continuum of external modes is driven by a saturable pumping mechanism. In the dilute flux regime, where atom-atom interactions are negligible in the output, we have been able to solve this model without making the Born-Markov approximation. The more exact treatment has a different effective damping rate and occupation of the lasing mode, as well as a shifted frequency and linewidth of the output. We examine gravitational damping numerically, finding linewidths and frequency shifts for a range of pumping rates. We treat mean field damping analytically, finding a memory function for the Thomas-Fermi regime. The occupation and linewidth are found to have a nonlinear scaling behavior which has implications for the stability of atom lasers.