We have published an experimental study into the specific heat of a harmonically trapped Bose gas. Our experiment was sensitive enough to measure the correction to the specific heat caused by atom-atom interactions. Link to the article here: http://journals.aps.org/pra/abstract/10.1103/PhysRevA.92.063622 or to the preprint here: http://arxiv.org/abs/1409.5494
Our paper entitled
is now published in New Journal of Physics. This is an open access journal, so anyone can read it. It has a nice video that explains some of the basic concepts.
Direct measurement of the heat capacity of a Bose-Einstein condensate
S. K. Ruddell,∗ D. H. White, A. Ullah,† and M. D. Hoogerland Department of Physics, University of Auckland, Private Bag 92019, Auckland, New Zealand
We transfer a known quantity of energy to a harmonically trapped Bose-Einstein condensate in order to study the resulting thermodynamics. We consider two methods, the first using a free expansion under gravity and the second using an optical standing wave to diffract the atoms in the potential. We investigate the effect of interactions on the resulting thermodynamics and compare our results to theory, with no adjustable parameters, providing a quantitative analysis of the heat capacity of our system.
We submitted a new paper on phase noise in the delta kicked rotor. It can be found on the archive here: http://arxiv.org/abs/1407.1921
A new Centre of Research Excellence has been funded, the Dodd-Walls Centre for Photonic and Quantum Technologies. See a newspaper article here. The CoRE will bring significant new funding to the lab.
The Anderson localisation proposal was funded with room for a postdoc! Watch this space for news
By adding an adjustable phase to the delta-kicked rotor experiment we were able to generate a “flying island” of stability in this classically chaotic system. The results were published here:
Our all-optical BEC has been back for a little while, no real problems. We had some standard issues of shutters not shutting at the appropriate time, and magnetic fields not being what they should be, but everything is up and running. Atom numbers are comparable to previously, and we’re working on improving this.
After a lot of mucking around with overhead tables, the new labs overheating and non-working water cooling, we finally have both magneto-optical traps working. The dipole trap is lined up and ready to go. So BEC soon we hope.
We have moved the lab to the basement. The vacuum got shifted in one piece!
