Atomic population distribution in the output ports of cold-atom interferometers with optical splitting and recombination

TL;DR

This paper derives and analyzes the probability distribution of atom populations in the output ports of cold-atom interferometers, highlighting how interactions and phase shifts influence the distribution, with comparisons to experimental data.

Contribution

It provides a theoretical framework for understanding atom population distributions in optical-split cold-atom interferometers, including effects of interactions and phase shifts.

Findings

Probability distribution depends on phase shift and interactions.

Distribution features reveal information about phase accumulation.

Results agree with experimental observations.

Abstract

Cold-atom interferometers with optical splitting and recombination use off-resonant laser beams to split a cloud of Bose-Einstein condensate (BEC) into two clouds that travel along different paths and are then recombined again using optical beams. After the recombination, the BEC in general populates both the cloud at rest and the moving clouds. Measuring relative number of atoms in each of these clouds yields information about the relative phase shift accumulated by the atoms in the two moving clouds during the interferometric cycle. We derive the expression for the probability of finding any given number of atoms in each of the clouds, discuss features of the probability density distribution, analyze its dependence on the relative accumulated phase shift as a function of the strength of the interatomic interactions, and compare our results with experiment.