Correlation Dynamics and Single-Atom Detection with Ultracold Metastable Helium

Abstract

Correlation functions are a useful tool to investigate the interaction statistics in a quantum many-body system such as ultracold atoms. Historically, the study of coherence and correlations between pairs of photons in the famous Hanbury Brown and Twiss experiment was pioneering to the field of quantum optics. Since then, the area of quantum atom-optics has also gained momentum sparked by the development of lasers to cool atoms to ultra-low temperatures and the formation of Bose-Einstein condensate.

This thesis reports on progress towards an experiment to measure the second-order correlation function for a gas of ultracold metastable helium atoms. Metastable helium atoms are a unique system with single-atom detection capability that enables one to measure the correlation functions associated with the system. First, a numerical approach is taken to simulate the expected second-order correlation function for our system with given experimental parameters. The experimental sequence is then characterised and optimised to allow for the creation of a BEC. This is followed by the installation, optimisation and characterisation of the microchannel plates and delay-line detector for far-field single-atom detection and the measurement of correlation functions. This setup will form a powerful tool that can be used to perform exciting experiments with correlation functions once some minor technical issues have been resolved.