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arXiv · 2008.02631

Spin-orbit implementation of Solovay-Kitaev decomposition of single-qubit channels

M. H. M. Passos·A. de Oliveira Junior·M. C. de Oliveira·A. Z. Khoury·J. A. O Huguenin
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Abstract

The Solovay-Kitaev theorem allows us to approximate any single-qubit gate to arbitrary accuracy with a finite sequence of fundamental operations from a universal set of gates. Inspired by this decomposition, we present a quantum channel simulator capable of implementing any completely positive trace-preserving map. Our realization consists of one ancillary qubit, encoded in the transverse mode of a laser beam (orbital degree of freedom), one qubit system, encoded in its polarization (spin), one spin-orbit CNOT gate and four single-qubit operations performed with prisms and polarization components. Our results describe the implementation of arbitrary single-qubit channels on the photon polarization using the transverse mode as the ancillary qubit.

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M. H. M. Passos, A. de Oliveira Junior, M. C. de Oliveira, A. Z. Khoury, J. A. O Huguenin. 2020-08-06. Spin-orbit implementation of Solovay-Kitaev decomposition of single-qubit channels. https://doi.org/10.1103/physreva.102.062601

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