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arXiv:2011.13746 · Physical Review A

Variational analysis of driven-dissipative bosonic fields

Tim Pistorius, Hendrik Weimer

Published Dec 22, 2021• 1 citation
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Abstract

We present a method to perform a variational analysis of the quantum master equation for driven-disspative bosonic fields with arbitrary large occupation numbers. Our approach combines the $P$ representation of the density matrix and the variational principle for open quantum system. We benchmark the method by comparing it to wave-function Monte Carlo simulations and the solution of the Maxwell-Bloch equation for the Jaynes-Cummings model. Furthermore, we study a model describing Rydberg polaritons in a cavity field and introduce an additional set of variational parameters to describe correlations between different modes.

DOI
10.1103/physreva.104.063711

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We present a new paradigm for the dynamical simulation of interacting many-boson open quantum systems. The method relies on a variational ansatz for the nnn-boson density matrix, in terms of a superposition of photon-added coherent states. It is most efficient for the simulation of driven-dissipative systems where the state is well described by quantum fluctuations on top of a displaced field, making it suitable for the simulation of several coupled modes with large occupation numbers, that are otherwise very challenging using a Fock-space expansion. We test our method on several examples, demonstrating its potential application to the predictive simulation of interacting bosonic systems and cat qubits.
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