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arXiv · 2303.06098

Experimental realization of nonunitary multi-qubit operations

Martin W. van Mourik·Elias Zapusek·Pavel Hrmo·Lukas Gerster·Rainer Blatt·Thomas Monz·Philipp Schindler·Florentin Reiter
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Abstract

We demonstrate a novel experimental toolset that enables irreversible multi-qubit operations on a quantum platform. To exemplify our approach, we realize two elementary nonunitary operations: the OR and NOR gates. The electronic states of two trapped $^{40}$Ca$^{+}$ ions encode the logical information, and a co-trapped $^{88}$Sr$^{+}$ ion provides the irreversibility of the gate by a dissipation channel through sideband cooling. We measure $87\%$ and $81\%$ success rates for the OR and NOR gates, respectively. The presented methods are a stepping stone towards other nonunitary operations such as in quantum error correction and quantum machine learning.

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Martin W. van Mourik, Elias Zapusek, Pavel Hrmo, Lukas Gerster, Rainer Blatt, Thomas Monz, Philipp Schindler, Florentin Reiter. 2023-03-10. Experimental realization of nonunitary multi-qubit operations. https://doi.org/10.1103/physrevlett.132.040602

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