Cold Collisions of Ultracold Atoms
Thomas, Ryan James

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Thomas, R. J. (2017). Cold Collisions of Ultracold Atoms (Thesis, Doctor of Philosophy). University of Otago. Retrieved from http://hdl.handle.net/10523/7776
Permanent link to OUR Archive version:
http://hdl.handle.net/10523/7776
Abstract:
This thesis describes experiments investigating the collisions of alkali metal atoms at energies between 10 - 2000 uK, measured in units of the Boltzmann constant. The atoms are accelerated towards each other using a purpose-built collider comprised of a crossed-beam optical dipole trap, which enables us to collide dense ensembles of ultracold atoms in any internal state at relatively high energies. I present the results of two experiments centered around resonant enhancement of the collisions. The first is between homonuclear 40K atoms near a shape resonance where the fermionic nature of the atoms determines the character of multiple scattering effects. The second experiment involves heteronuclear 40K87Rb collisions near a magnetically-tunable Feshbach resonance where we measure parameters describing the resonance as a function of collision energy. Theoretical models are developed that let us describe the collisions using published empirical interaction potentials, and we find good agreement between these models and the experiment.
Date:
2017
Advisor:
Kjaergaard, Niels; Longdell, Jevon
Degree Name:
Doctor of Philosophy
Degree Discipline:
Physics
Publisher:
University of Otago
Keywords:
physics; bose-einstein condensation; atomic collisions; rubidum; potassium; coupled-channels equations; feshbach resonances; shape resonances
Research Type:
Thesis
Languages:
English
Collections
- Physics [120]
- Thesis - Doctoral [3038]