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Magnetic tuning of tunnel coupling between InAsP double quantum dots in InP nanowires.

ABSTRACT: We study experimentally and theoretically the in-plane magnetic field dependence of the coupling between dots forming a vertically stacked double dot molecule. The InAsP molecule is grown epitaxially in an InP nanowire and interrogated optically at millikelvin temperatures. The strength of interdot tunneling, leading to the formation of the bonding-antibonding pair of molecular orbitals, is investigated by adjusting the sample geometry. For specific geometries, we show that the interdot coupling can be controlled in-situ using a magnetic field-mediated redistribution of interdot coupling strengths. This is an important milestone in the development of qubits required in future quantum information technologies.

SUBMITTER: Phoenix J

PROVIDER: S-EPMC8948226 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Magnetic tuning of tunnel coupling between InAsP double quantum dots in InP nanowires.

Phoenix Jason J Korkusinski Marek M Dalacu Dan D Poole Philip J PJ Zawadzki Piotr P Studenikin Sergei S Williams Robin L RL Sachrajda Andrew S AS Gaudreau Louis L

Scientific reports 20220324 1

We study experimentally and theoretically the in-plane magnetic field dependence of the coupling between dots forming a vertically stacked double dot molecule. The InAsP molecule is grown epitaxially in an InP nanowire and interrogated optically at millikelvin temperatures. The strength of interdot tunneling, leading to the formation of the bonding-antibonding pair of molecular orbitals, is investigated by adjusting the sample geometry. For specific geometries, we show that the interdot coupling ...[more]

PMID: 35332174

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