-
[show abstract]
[hide abstract]
ABSTRACT: Using the unique detection properties offered by metastable helium atoms we have produced high resolution images of the transverse spatial profiles of an atom laser beam. We observe fringes on the beam, resulting from quantum mechanical interference between atoms that start from rest at different transverse locations within the outcoupling surface and end up at a later time with different velocities at the same transverse position. Numerical simulations in the low output-coupling limit give good quantitative agreement with our experimental data.
Optics Express 15.26 (2007): 17673-17680.
-
[show abstract]
[hide abstract]
ABSTRACT: We solve the Gross-Pitaevskii equation numerically for the collapse induced by a switch from positive to negative scattering lengths. We compare our results with experiments performed with Bose-Einstein condensates of 85Rb, in which the scattering length was controlled using a Feshbach resonance. Building on previous theoretical work we identify quantitative differences between the predictions of mean-field theory and the results of the experiments. In addition to the previously reported difference between the predicted and observed critical atom number for collapse, we also find that the predicted collapse times systematically exceed those observed experimentally.
Physical Review A 67.1 (2003): 014304/1-4.
-
Robins,
Nicholas,
Faculty of Science,
Department of Physics,
Figl,
Haine,
Morrison,
Adele,
Jeppesen, Hope,
Joseph,
Close,
John
[show abstract]
[hide abstract]
ABSTRACT: In this Letter we present experimental results and a simple analytic theory on the first continuous (long pulse) Raman atom laser. We analyze the flux and brightness of a generic two state atom laser with an analytic model that shows excellent agreement with our experiments. We show that, for the same source size, the brightness achievable with a Raman atom laser is at least 3 orders of magnitude greater than achievable in any other demonstrated continuously outcoupled atom laser.
Physical Review Letters 96.14 (2006): 140403/1-4.
-
[show abstract]
[hide abstract]
ABSTRACT: We introduce a scheme for creating continuous variable entanglement between an atomic beam and an optical field, by using squeezed light to outcouple atoms from a Bose-Einstein condensate via a Raman transition. We model the full multimode dynamics of the atom laser beam and the squeezed optical field and show that, with appropriate two-photon detuning and two-photon Rabi frequency, the transmitted light is entangled in amplitude and phase with the outcoupled atom laser beam. The degree of entanglement is controllable via changes in the two-photon Rabi frequency of the outcoupling process.
Physical Review Letters 96.13 (2006): 133601/1-4.
-
Hetet,
Gabriel,
Faculty of Science,
Department of Physics,
Peng,
Amy,
Johnsson,
Mattias, Hope,
Joseph,
Lam,
Ping Koy
[show abstract]
[hide abstract]
ABSTRACT: We present a quantum multimodal treatment describing electromagnetically induced transparency EIT as a mechanism for storing continuous-variable quantum information in light fields. Taking into account the atomic noise and decoherences of realistic experiments, we numerically model the propagation, storage, and readout of signals contained in the sideband amplitude and phase quadratures of a light pulse using phase space methods. An analytical treatment of the effects predicted by this model is then presented. Finally, we use quantum information benchmarks to examine the properties of the EIT-based memory and show the parameters needed to operate beyond the quantum limit.
Physical Review A 77.1 (2008): 012323/1-16.
