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Implementation of quantum maps by programmable quantum processors

Mark Hillery·Mario Ziman·Vladimir Buzek
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Abstract

A quantum processor is a device with a data register and a program register. The input to the program register determines the operation, which is a completely positive linear map, that will be performed on the state in the data register. We develop a mathematical description for these devices, and apply it to several different examples of processors. The problem of finding a processor that will be able to implement a given set of mappings is also examined, and it is shown that while it is possible to design a finite processor to realize the phase-damping channel, it is not possible to do so for the amplitude-damping channel.

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Mark Hillery, Mario Ziman, Vladimir Buzek. 2002-05-09. Implementation of quantum maps by programmable quantum processors. https://doi.org/10.1103/physreva.66.042302

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