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arXiv · 1710.04885

Optical holonomic single quantum gates with a geometric spin under a zero field

Yuhei Sekiguchi·Naeko Niikura·Ryota Kuroiwa·Hiroki Kano·Hideo Kosaka
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Abstract

Realization of fast fault-tolerant quantum gates on a single spin is the core requirement for solid-state quantum-information processing. As polarized light shows geometric interference, spin coherence is also geometrically controlled with light via the spin-orbit interaction. Here, we show that a geometric spin in a degenerate subspace of a spin-1 electronic system under a zero field in a nitrogen vacancy center in diamond allows implementation of optical non-adiabatic holonomic quantum gates. The geometric spin under quasi-resonant light exposure undergoes a cyclic evolution in the spin-orbit space, and acquires a geometric phase or holonomy that results in rotations about an arbitrary axis by any angle defined by the light polarization and detuning. This enables universal holonomic quantum gates with a single operation. We demonstrate a complete set of Pauli quantum gates using the geometric spin preparation and readout techniques. The new scheme opens a path to holonomic quantum computers and repeaters.

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Yuhei Sekiguchi, Naeko Niikura, Ryota Kuroiwa, Hiroki Kano, Hideo Kosaka. 2017-10-13. Optical holonomic single quantum gates with a geometric spin under a zero field. https://doi.org/10.1038/nphoton.2017.40

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