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arXiv · 0812.1457

Experimental realization of programmable quantum gate

Michal Micuda·Miroslav Jezek·Miloslav Dusek·Jaromir Fiurasek
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Abstract

We experimentally demonstrate a programmable single-qubit quantum gate. This device applies a unitary phase shift operation to a data qubit with the value of the phase shift being fully determined by the state of a program qubit. Our linear optical implementation is based on the encoding of qubits into polarization states of single photons, two-photon interference on a polarizing beam splitter, and measurement on the output program qubit. We fully characterize the programmable gate by quantum process tomography. The achieved average quantum process fidelity exceeding 97% illustrates very good performance of the gate for all values of the encoded phase shift. We also show that by using a different set of program states the device can operate as a programmable partial polarization filter.

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Michal Micuda, Miroslav Jezek, Miloslav Dusek, Jaromir Fiurasek. 2008-12-08. Experimental realization of programmable quantum gate. https://doi.org/10.1103/physreva.78.062311

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