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arXiv · 1210.2632

Decoherence-free linear quantum subsystems

Naoki Yamamoto
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Abstract

This paper provides a general theory for characterizing and constructing a decoherence-free (DF) subsystem for an infinite dimensional linear open quantum system. The main idea is that, based on the Heisenberg picture of the dynamics rather than the commonly-taken Schrodinger picture, the notions of controllability and observability in control theory are employed to characterize a DF subsystem. A particularly useful result is a general if and only if condition for a linear system to have a DF component; this condition is used to demonstrate how to actually construct a DF dynamics in some specific examples. It is also shown that, as in the finite dimensional case, we are able to do coherent manipulation and preservation of a state of a DF subsystem.

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Naoki Yamamoto. 2014-03-25. Decoherence-free linear quantum subsystems. https://doi.org/10.1109/tac.2014.2313218

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