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Generalized measurements via programmable quantum processor

Marian Rosko·Vladimir Buzek·Paul Robert Chouha·Mark Hillery
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Abstract

We show that it is possible to control the trade-off between information gain and disturbance in generalized measurements of qudits by utilizing the programmable quantum processor. This universal quantum machine allows us to perform a generalized measurement on the initial state of the input qudit to construct a Husimi function of this state. The trade-off between the gain and the disturbance of the qudit is controlled by the initial state of ancillary system that acts as a program register for the quantum-information distributor. The trade-off fidelity does not depend on the initial state of the qudit.

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Marian Rosko, Vladimir Buzek, Paul Robert Chouha, Mark Hillery. 2003-11-25. Generalized measurements via programmable quantum processor. https://doi.org/10.1103/physreva.68.062302

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