Location Qubits in a Multiple-Quantum-Dot System

Nano Lett. 2024 May 8;24(18):5656-5661. doi: 10.1021/acs.nanolett.4c01272. Epub 2024 Apr 24.

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 are robust against the main decoherence mechanisms, and realistic single-qubit gate fidelities exceed 99.9%. Our scheme paves a clear way toward constructing multiqubit solid-state quantum registers with a built-in photonic interface─a key building block of the forthcoming quantum Internet.

Keywords: Optically active nanowire quantum dots; adiabatic Raman technique; crystal-phase quantum structure; location qubit; optical quantum control.