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arXiv · 1002.4436

Selective and efficient quantum process tomography with single photons

Christian Tomás Schmiegelow·Miguel Antonio Larotonda·Juan Pablo Paz
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Abstract

We present the results of the first photonic implementation of a new method for quantum process tomography. The method (originally presented by A. Bendersky et al, Phys. Rev. Lett 100, 190403 (2008)) enables the estimation of any element of the chi-matrix that characterizes a quantum process using resources that scale polynomially with the number of qubits. It is based on the idea of mapping the estimation of any chi-matrix element onto the average fidelity of a quantum channel and estimating the latter by sampling randomly over a special set of states called a 2-design. With a heralded single photon source we fully implement such algorithm and perform process tomography on a number of channels affecting the polarization qubit. The method is compared with other existing ones and its advantages are discussed.

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Christian Tomás Schmiegelow, Miguel Antonio Larotonda, Juan Pablo Paz. 2010-02-23. Selective and efficient quantum process tomography with single photons. https://arxiv.org/abs/1002.4436

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