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Zero Field Splitting of Heavy-Hole States in Quantum Dots.

ABSTRACT: Using inelastic cotunneling spectroscopy we observe a zero field splitting within the spin triplet manifold of Ge hut wire quantum dots. The states with spin ±1 in the confinement direction are energetically favored by up to 55 ?eV compared to the spin 0 triplet state because of the strong spin-orbit coupling. The reported effect should be observable in a broad class of strongly confined hole quantum-dot systems and might need to be considered when operating hole spin qubits.

SUBMITTER: Katsaros G

PROVIDER: S-EPMC7349564 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Zero Field Splitting of Heavy-Hole States in Quantum Dots.

Katsaros Georgios G Kukučka Josip J Vukušić Lada L Watzinger Hannes H Gao Fei F Wang Ting T Zhang Jian-Jun JJ Held Karsten K

Nano letters 20200611 7

Using inelastic cotunneling spectroscopy we observe a zero field splitting within the spin triplet manifold of Ge hut wire quantum dots. The states with spin ±1 in the confinement direction are energetically favored by up to 55 μeV compared to the spin 0 triplet state because of the strong spin-orbit coupling. The reported effect should be observable in a broad class of strongly confined hole quantum-dot systems and might need to be considered when operating hole spin qubits. ...[more]

PMID: 32479090

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