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arXiv · 1105.6015

A general approach to quantum dynamics using a variational master equation: Application to phonon-damped Rabi rotations in quantum dots

Dara P. S. McCutcheon·Nikesh S. Dattani·Erik M. Gauger·Brendon W. Lovett·Ahsan Nazir
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Abstract

We develop a versatile master equation approach to describe the non-equilibrium dynamics of a two-level system in contact with a bosonic environment, which allows for the exploration of a wide range of parameter regimes within a single formalism. As an experimentally relevant example, we apply this technique to the study of excitonic Rabi rotations in a driven quantum dot, and compare its predictions to the numerical Feynman integral approach. We find excellent agreement between the two methods across a generally difficult range of parameters. In particular, the variational master equation technique captures effects usually considered to be non-perturbative, such as multi-phonon processes and bath-induced driving renormalisation, and can give reliable results even in regimes in which previous master equation approaches fail.

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Dara P. S. McCutcheon, Nikesh S. Dattani, Erik M. Gauger, Brendon W. Lovett, Ahsan Nazir. 2011-05-30. A general approach to quantum dynamics using a variational master equation: Application to phonon-damped Rabi rotations in quantum dots. https://doi.org/10.1103/physrevb.84.081305

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