Optimal estimation of one parameter quantum channels

Mohan Sarovar, G. J. Milburn

备注：: 23 pages, 4 figures. Published version
发表信息：: J. Phys. A: Math. Gen. 39 (2006) 8487-8505
DOI：: 10.1088/0305-4470/39/26/015

英文摘要：

We explore the task of optimal quantum channel identification, and in particular the estimation of a general one parameter quantum process. We derive new characterizations of optimality and apply the results to several examples including the qubit depolarizing channel and the harmonic oscillator damping channel. We also discuss the geometry of the problem and illustrate the usefulness of using entanglement in process estimation.

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