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arXiv · 2107.05960

Location qubits in a multi-quantum-dot system

Dayang Li·Nika Akopian
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Abstract

A physical platform for nodes of the envisioned quantum internet is long-sought. Here we propose such a platform, along with a conceptually simple and experimentally uncomplicated quantum information processing scheme, realized in a system of multiple crystal-phase quantum dots. We introduce novel location qubits, describe a method to construct a universal set of all-optical quantum gates, and simulate their performance in realistic structures, including decoherence sources. Our results show that location qubits can maintain coherence 5 orders of magnitude longer than single-qubit operation time, and single-qubit gate errors do not exceed 0.01%. Our scheme paves a clear way towards constructing multi-qubit solid-state quantum systems with a built-in photonic interface, such as a multi-qubit quantum register -- a key building block of the forthcoming quantum internet.

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Dayang Li, Nika Akopian. 2021-07-13. Location qubits in a multi-quantum-dot system. https://arxiv.org/abs/2107.05960

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