2013/05/31 by A. Chantasri, J. Dressel, A. N. Jordan
Physics and Astronomy · #quant-ph #cond-mat.mes-hall #cond-mat.stat-mech
paper · pdf · doi:10.1103/physreva.88.042110
published as Phys. Rev. A 88, 042110 (2013) · Published version. 8 pages, 3 figures, movies available at http://youtu.be/OQ3PwkSKEUw and http://youtu.be/sTlV2amQtjQ
arxiv created 2013/10/14 · arxiv updated 2013/10/16
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.