Qubit feedback and control with kicked quantum nondemolition measurements: A quantum Bayesian analysis
Mesoscale and Nanoscale Physics
2007-05-23 v1 Quantum Physics
Abstract
The informational approach to continuous quantum measurement is derived from POVM formalism for a mesoscopic scattering detector measuring a charge qubit. Quantum Bayesian equations for the qubit density matrix are derived, and cast into the form of a stochastic conformal map. Measurement statistics are derived for kicked quantum nondemolition measurements, combined with conditional unitary operations. These results are applied to derive a feedback protocol to produce an arbitrary pure state after a weak measurement, as well as to investigate how an initially mixed state becomes purified with and without feedback.
Cite
@article{arxiv.cond-mat/0606676,
title = {Qubit feedback and control with kicked quantum nondemolition measurements: A quantum Bayesian analysis},
author = {Andrew N. Jordan and Alexander N. Korotkov},
journal= {arXiv preprint arXiv:cond-mat/0606676},
year = {2007}
}
Comments
13 pages, 3 figures