Coherent Atomic Manipulation and Cooling

This work unites the concepts of laser cooling and matter-wave interferometry to develop an interferometric laser cooling technique in an experimental system of cold rubidium atoms. Serving as an introduction to graduate level coherent optical atomic manipulation, the thesis describes the theory of stimulated Raman transitions and atom interferometry, along with the experimental methods for preparing and manipulating cold atoms, before building on these foundations to explore tailored optical pulse sequences and novel atomic cooling techniques.Interferometric cooling, originally proposed by Weitz and Hänsch in 2000, is based upon the coherent broadband laser pulses of Ramsey interferometry and in principle allows laser cooling of atomic and molecular species outside the scope of traditional Doppler laser cooling. On the path toward cooling, composite pulses – quantum error correction methods, developed by chemists to mitigate the effects of in homogeneities in NMR spectroscopy – are investigated with a view to improving the performance of atom interferometers.

Alex's academic career to date has spanned a range of disciplines within atomic, molecular and optical physics, including, in order: optical tweezing with nanofibers and dipole trapping of microspheres as an undergraduate in the groups of Phil Jones and Peter Barker at University College London; cold atom interferometry and composite pulses as a graduate in the group of Tim Freegarde at the University of Southampton; and hybrid atom-ion trapping, cold chemistry, and molecular spectroscopy as a post-doc in the group of Eric Hudson at the University of California, Los Angeles.