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arXiv · 1707.06479

Device Architecture for Coupling Spin Qubits Via an Intermediate Quantum State

X. G. Croot·S. J. Pauka·J. D. Watson·G. C. Gardner·S. Fallahi·M. J. Manfra·D. J. Reilly
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Abstract

We demonstrate a scalable device architecture that facilitates indirect exchange between singlet-triplet spin qubits, mediated by an intermediate quantum state. The device comprises five quantum dots, which can be independently loaded and unloaded via tunneling to adjacent reservoirs, avoiding charge latch-up common in linear dot arrays. In a step towards realizing two-qubit entanglement based on indirect exchange, the architecture permits precise control over tunnel rates between the singlet-triplet qubits and the intermediate state. We show that by separating qubits by 1 um, the residual capacitive coupling between them is reduced to 7 ueV.

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X. G. Croot, S. J. Pauka, J. D. Watson, G. C. Gardner, S. Fallahi, M. J. Manfra, D. J. Reilly. 2017-07-20. Device Architecture for Coupling Spin Qubits Via an Intermediate Quantum State. https://doi.org/10.1103/physrevapplied.10.044058

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