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arXiv · 1506.04737

A transverse Hamiltonian variational technique for open quantum stochastic systems and its application to coherent quantum control

Igor G. Vladimirov
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Abstract

This paper is concerned with variational methods for nonlinear open quantum systems with Markovian dynamics governed by Hudson-Parthasarathy quantum stochastic differential equations. The latter are driven by quantum Wiener processes of the external boson fields and are specified by the system Hamiltonian and system-field coupling operators. We consider the system response to perturbations of these energy operators and introduce a transverse Hamiltonian which encodes the propagation of the perturbations through the unitary system-field evolution. This provides a tool for the infinitesimal perturbation analysis and development of optimality conditions for coherent quantum control problems. We apply the transverse Hamiltonian variational technique to a mean square optimal coherent quantum filtering problem for a measurement-free cascade connection of quantum systems.

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Igor G. Vladimirov. 2015-06-15. A transverse Hamiltonian variational technique for open quantum stochastic systems and its application to coherent quantum control. https://doi.org/10.1109/cca.2015.7320611

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