Korppi, Maria. Optomechanical coupling between ultracold atoms and a membrane oscillator. 2014, PhD Thesis, University of Basel, Faculty of Science.
Official URL: http://edoc.unibas.ch/diss/DissB_10771
When the trap frequency of the atoms is matched to the membrane frequency, we observe resonant energy transfer. In addition, by applying simultaneous laser cooling to the atoms, we can dissipate energy from the coupled system leading to sympathetic cooling of the membrane mode. The experimental data follows the theoretical estimations that predict the coupling to scale with the number of trapped atoms. Furthermore, by including the finite temperature of the atoms and their spatially inhomogeneous trapping potential in the theoretical model of the optomechanical coupling, we can accurately describe the width and shape of the resonance.
In an improved experimental setup, the membrane is enclosed in a cavity while the atoms are trapped in the standing wave lattice outside the cavity. The presence of the cavity results in a considerable enhancement of the coupling strength in proportion to the cavity finesse. So far we have observed sympathetic cooling of the membrane mode by a factor of 32 starting from room temperature. Theoretical estimates show that in such a setup ground-state cooling of the membrane mode should be possible, allowing one to access the quantum coherent coupling regime.
|Committee Members:||Heidmann, A.|
|Faculties and Departments:||05 Faculty of Science > Departement Physik > Physik > Experimentelle Nanophysik (Treutlein)|
|Bibsysno:||Link to catalogue|
|Number of Pages:||194 S.|
|Last Modified:||30 Jun 2016 10:55|
|Deposited On:||12 May 2014 12:01|
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