Eigenmode description of Raman scattering in atomic vapors in the presence of decoherence

TL;DR

This paper presents a theoretical model for Raman scattering in atomic vapors that accounts for decoherence, analyzing spatial modes and noise effects in cold and room-temperature atoms for quantum memory applications.

Contribution

It introduces a novel theoretical framework that separates time evolution from spatial degrees of freedom in Raman scattering with decoherence effects included.

Findings

Spatial eigenmodes of Stokes photons are computed.

Decoherence impacts the temporal properties of the scattering process.

Model applied to ultra-cold and room-temperature atomic systems.

Abstract

A theoretical model describing the Raman scattering process in atomic vapors is constructed. The treatment investigates the low-excitation regime suitable for modern experimental applications. Despite the incorporated decoherence effects (possibly mode dependent) it allows for a direct separation of the time evolution from the spatial degrees of freedom. The impact of noise on the temporal properties of the process is examined. The model is applied in two experimentally relevant situations of ultra-cold and room-temperature atoms. The spatial eigenmodes of the Stokes photons and their coupling to atomic excitations are computed. Similarly, dynamics and the waveform of the collective atomic state are derived for quantum memory implementations.