Lindbladian approximation beyond ultra-weak coupling
- URL: http://arxiv.org/abs/2012.14208v4
- Date: Thu, 10 Jun 2021 11:37:30 GMT
- Title: Lindbladian approximation beyond ultra-weak coupling
- Authors: Tobias Becker, Ling-Na Wu, Andr\'e Eckardt
- Abstract summary: Lindblad-type equations provide the most general class of Markovian MEs.
Lindblad-type MEs are commonly derived from the Born-Markov-Redfield equation via a rotating-wave approximation (RWA)
Here we derive an alternative Lindbladian approximation to the Redfield equation, which does not rely on ultra-weak system-bath coupling.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Away from equilibrium, the properties of open quantum systems depend on the
details of their environment. A microscopic derivation of a master equation
(ME) is therefore crucial. Of particular interest are Lindblad-type equations,
not only because they provide the most general class of Markovian MEs, but also
since they are the starting point for efficient quantum trajectory simulations.
Lindblad-type MEs are commonly derived from the Born-Markov-Redfield equation
via a rotating-wave approximation (RWA). However the RWA is valid only for
ultra-weak system bath coupling and often fails to accurately describe
nonequilibrium processes. Here we derive an alternative Lindbladian
approximation to the Redfield equation, which does not rely on ultra-weak
system-bath coupling. Applying it to an extended Hubbard model coupled to Ohmic
baths, we show that, especially away from equilibrium, it provides a good
approximation in large parameter regimes where the RWA fails.
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