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arXiv · 0910.4440

First-principles quantum dynamics for fermions: Application to molecular dissociation

M. Ogren·K. V. Kheruntsyan·J. F. Corney
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Abstract

We demonstrate that the quantum dynamics of a many-body Fermi-Bose system can be simulated using a Gaussian phase-space representation method. In particular, we consider the application of the mixed fermion-boson model to ultracold quantum gases and simulate the dynamics of dissociation of a Bose-Einstein condensate of bosonic dimers into pairs of fermionic atoms. We quantify deviations of atom-atom pair correlations from Wick's factorization scheme, and show that atom-molecule and molecule-molecule correlations grow with time, in clear departures from pairing mean-field theories. As a first-principles approach, the method provides benchmarking of approximate approaches and can be used to validate dynamical probes for characterizing strongly correlated phases of fermionic systems.

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M. Ogren, K. V. Kheruntsyan, J. F. Corney. 2011-03-16. First-principles quantum dynamics for fermions: Application to molecular dissociation. https://doi.org/10.1209/0295-5075%2F92%2F36003

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