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arXiv · 1112.0380

Quantum dynamics in ultra-cold atomic physics

Q. Y. He·M. D. Reid·B. Opanchuk·R. Polkinghorne·Laura E. C. Rosales-Zárate·P. D. Drummond
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Abstract

We review recent developments in the theory of quantum dynamics in ultra-cold atomic physics, including exact techniques, but focusing on methods based on phase-space mappings that are appli- cable when the complexity becomes exponentially large. These phase-space representations include the truncated Wigner, positive-P and general Gaussian operator representations which can treat both bosons and fermions. These phase-space methods include both traditional approaches using a phase-space of classical dimension, and more recent methods that use a non-classical phase-space of increased dimensionality. Examples used include quantum EPR entanglement of a four-mode BEC, time-reversal tests of dephasing in single-mode traps, BEC quantum collisions with up to 106 modes and 105 interacting particles, quantum interferometry in a multi-mode trap with nonlinear absorp- tion, and the theory of quantum entropy in phase-space. We also treat the approach of variational optimization of the sampling error, giving an elementary example of a nonlinear oscillator.

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Q. Y. He, M. D. Reid, B. Opanchuk, R. Polkinghorne, Laura E. C. Rosales-Zárate, P. D. Drummond. 2011-12-02. Quantum dynamics in ultra-cold atomic physics. https://doi.org/10.1007/s11467-011-0232-x

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