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arXiv · 2505.05875

Inferring charge-noise source locations from correlations in spin qubits

Juan S. Rojas-Arias·Akito Noiri·Jun Yoneda·Peter Stano·Takashi Nakajima·Kenta Takeda·Takashi Kobayashi·Giordano Scappucci·Seigo Tarucha·Daniel Loss
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Abstract

We investigate low-frequency noise in a spin-qubit device made in isotopically purified Si/Si-Ge. Observing sizable cross-correlations among energy fluctuations of different qubits, we conclude that these fluctuations are dominated by charge noise. At low frequencies, the noise spectra are not well described by a power law; instead, they reveal the presence of a few individual two-level fluctuators (TLFs). We demonstrate that the noise cross-correlations allow one to get information on the spatial location of such individual TLFs.

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Juan S. Rojas-Arias, Akito Noiri, Jun Yoneda, Peter Stano, Takashi Nakajima, Kenta Takeda, Takashi Kobayashi, Giordano Scappucci, Seigo Tarucha, Daniel Loss. 2025-05-09. Inferring charge-noise source locations from correlations in spin qubits. https://doi.org/10.1103/glp5-bb5b

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