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arXiv · 1305.5201

Action principle for continuous quantum measurement

A. Chantasri·J. Dressel·A. N. Jordan
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Abstract

We present a stochastic path integral formalism for continuous quantum measurement that enables the analysis of rare events using action methods. By doubling the quantum state space to a canonical phase space, we can write the joint probability density function of measurement outcomes and quantum state trajectories as a phase space path integral. Extremizing this action produces the most-likely paths with boundary conditions defined by preselected and postselected states as solutions to a set of ordinary differential equations. As an application, we analyze continuous qubit measurement in detail and examine the structure of a quantum jump in the Zeno measurement regime.

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A. Chantasri, J. Dressel, A. N. Jordan. 2013-10-14. Action principle for continuous quantum measurement. https://doi.org/10.1103/physreva.88.042110

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