Sub-Poissonian atom number fluctuations by three-body loss in mesoscopic ensembles

TL;DR

This paper demonstrates that three-body loss in ultracold atomic ensembles causes sub-Poissonian fluctuations in atom numbers, with experimental results aligning with theoretical predictions, advancing quantum information research with mesoscopic systems.

Contribution

It provides experimental evidence and theoretical analysis showing three-body loss induces sub-Poissonian atom number fluctuations in dense ultracold ensembles.

Findings

Measured Fano factor of 0.53±0.22 indicating sub-Poissonian fluctuations

Experimental results agree with analytic theory predicting F=3/5

Enables potential applications in quantum information science

Abstract

We show that three-body loss of trapped atoms leads to sub-Poissonian atom number fluctuations. We prepare hundreds of dense ultracold ensembles in an array of magnetic microtraps which undergo rapid three-body decay. The shot-to-shot fluctuations of the number of atoms per trap are sub-Poissonian, for ensembles comprising 50--300 atoms. The measured relative variance or Fano factor $F=0.53\pm 0.22$ agrees very well with the prediction by an analytic theory ($F=3/5$) and numerical calculations. These results will facilitate studies of quantum information science with mesoscopic ensembles.