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arXiv · 1803.10062

Quantum process tomography via completely positive and trace-preserving projection

George C. Knee·Eliot Bolduc·Jonathan Leach·Erik M. Gauger
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Abstract

We present an algorithm for projecting superoperators onto the set of completely positive, trace-preserving maps. When combined with gradient descent of a cost function, the procedure results in an algorithm for quantum process tomography: finding the quantum process that best fits a set of sufficient observations. We compare the performance of our algorithm to the diluted iterative algorithm as well as second-order solvers interfaced with the popular CVX package for MATLAB, and find it to be significantly faster and more accurate while guaranteeing a physical estimate.

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George C. Knee, Eliot Bolduc, Jonathan Leach, Erik M. Gauger. 2018-03-27. Quantum process tomography via completely positive and trace-preserving projection. https://doi.org/10.1103/physreva.98.062336

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