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arXiv · 0812.1096

Non-Markovian weak coupling limit of quantum Brownian motion

Sabrina Maniscalco·Jyrki Piilo·Kalle-Antti Suominen
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Abstract

We derive and solve analytically the non-Markovian master equation for harmonic quantum Brownian motion proving that, for weak system-reservoir couplings and high temperatures, it can be recast in the form of the master equation for a harmonic oscillator interacting with a squeezed thermal bath. This equivalence guarantees preservation of positivity of the density operator during the time evolution and allows one to establish a connection between the dynamics of Schrödinger cat states in squeezed environments and environment-induced decoherence in quantum Brownian motion.

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Sabrina Maniscalco, Jyrki Piilo, Kalle-Antti Suominen. 2008-12-05. Non-Markovian weak coupling limit of quantum Brownian motion. https://doi.org/10.1140/epjd%2Fe2009-00230-6

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