Phase Evolution in Spatial Dark States

TL;DR

This paper explores the phase evolution in spatial dark states during adiabatic processes, demonstrating how phase dynamics can be engineered alongside density transfer in multi-level atomic systems.

Contribution

It generalizes the STIRAP process to atomic states with complex phase distributions, highlighting the importance of phase dynamics in adiabatic state transfer.

Findings

Dark state density transfer is achievable despite phase dynamics.

Phase superposition states can be engineered through combined adiabatic and non-adiabatic processes.

Phase evolution must be considered as a dynamical process in spatial dark states.

Abstract

Adiabatic techniques using multi-level systems have recently been generalised from the optical case to settings in atom optics, solid state and even classical electrodynamics. The most well known example of these is the so called STIRAP process, which allows transfer of a particle between different states with large fidelity. Here we generalise and examine this process for an atomic centre-of-mass state with a non-trivial phase distribution and show that even though dark state dynamics can be achieved for the atomic density, the phase dynamics will still have to be considered as a dynamical process. In particular we show that the combination of adiabatic and non-adiabatic behaviour can be used to engineer phase superposition states.