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arXiv · 2406.14948

Identifying impurities in a silicon substrate by using a superconducting flux qubit

Hiraku Toida·Kosuke Kakuyanagi·Leonid V. Abdurakhimov·Masahiro Hori·Yukinori Ono·Shiro Saito
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Abstract

A bismuth-doped silicon substrate was analyzed by using a magnetometer based on a superconducting flux qubit. The temperature dependence of the magnetization indicates that the silicon substrate contains at least two signal sources, intentionally doped bismuth spins and a spin 1/2 system with a ratio of 0.873 to 0.127. In combination with a conventional electron spin resonance spectrometer, a candidate origin of the spin 1/2 system was identified as a dangling bond on the silicon surface. In addition, the spin sensitivity of the magnetometer was also estimated to be 12 spins/$\sqrt{\mathrm{Hz}}$ by using optimized dispersive readout.

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Hiraku Toida, Kosuke Kakuyanagi, Leonid V. Abdurakhimov, Masahiro Hori, Yukinori Ono, Shiro Saito. 2024-06-21. Identifying impurities in a silicon substrate by using a superconducting flux qubit. https://arxiv.org/abs/2406.14948

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