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arXiv · 2302.11717

Spatial noise correlations beyond nearest-neighbor in ${}^{28}$Si/SiGe spin qubits

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

We detect correlations in qubit-energy fluctuations of non-neighboring qubits defined in isotopically purified Si/SiGe quantum dots. At low frequencies (where the noise is strongest), the correlation coefficient reaches 10% for a next-nearest-neighbor qubit-pair separated by 200 nm. Assigning the observed noise to be of electrical origin, a simple theoretical model quantitatively reproduces the measurements and predicts a polynomial decay of correlations with interqubit distance. Our results quantify long-range correlations of noise dephasing quantum-dot spin qubits arranged in arrays, essential for scalability and fault-tolerance of such systems.

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Juan S. Rojas-Arias, Akito Noiri, Peter Stano, Takashi Nakajima, Jun Yoneda, Kenta Takeda, Takashi Kobayashi, Amir Sammak, Giordano Scappucci, Daniel Loss, Seigo Tarucha. 2023-02-23. Spatial noise correlations beyond nearest-neighbor in ${}^{28}$Si/SiGe spin qubits. https://doi.org/10.1103/physrevapplied.20.054024

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