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arXiv · 2411.16224

Charge-induced energy shift of a single-spin qubit under a magnetic-field gradient

Takashi Kobayashi·Akito Noiri·Takashi Nakajima·Kenta Takeda·Leon C. Camenzind·Ik Kyeong Jin·Giordano Scappucci·Seigo Tarucha
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Abstract

An electron confined by a semiconductor quantum dot (QD) can be displaced by changes in electron occupations of surrounding QDs owing to the Coulomb interaction. For a single-spin qubit in an inhomogeneous magnetic field, such a displacement of the host electron results in a qubit energy shift which must be handled carefully for high-fidelity operations. Here we spectroscopically investigate the qubit energy shift induced by changes in charge occupations of nearby QDs for a silicon single-spin qubit in a magnetic-field gradient. Between two different charge configurations of an adjacent double QD, a spin qubit shows an energy shift of about 4 MHz, which necessitates strict management of electron positions over a QD array. We confirm a correlation between the qubit frequency and the charge configuration by using a postselection analysis.

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Takashi Kobayashi, Akito Noiri, Takashi Nakajima, Kenta Takeda, Leon C. Camenzind, Ik Kyeong Jin, Giordano Scappucci, Seigo Tarucha. 2024-11-25. Charge-induced energy shift of a single-spin qubit under a magnetic-field gradient. https://doi.org/10.1103/physrevapplied.23.054078

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