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arXiv · 2411.10717

Systematic characterization of nanoscale $h$-BN quantum sensor spots created by helium-ion microscopy

Hao Gu·Moeta Tsukamoto·Yuki Nakamura·Shu Nakaharai·Takuya Iwasaki·Kenji Watanabe·Takashi Taniguchi·Shinichi Ogawa·Yukinori Morita·Kento Sasaki·Kensuke Kobayashi
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Abstract

The nanosized boron vacancy ($V_\mathrm{B}^-$) defect spot in hexagonal boron nitride ($h$-BN) is promising for a local magnetic field quantum sensor. One of its advantages is that a helium-ion microscope can make a spot at any location in an $h$-BN flake with nanometer accuracy. In this study, we investigate the properties of the created nanosized $V_\mathrm{B}^-$ defect spots by systematically varying three conditions: the helium-ion dose, the thickness of the $h$-BN flakes, and the substrate on which the $h$-BN flakes are attached. The physical background of the results obtained is successfully interpreted using Monte Carlo calculations. From the findings obtained here, a guideline for their optimal creation conditions is obtained to maximize its performance as a quantum sensor concerning sensitivity and localization.

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Hao Gu, Moeta Tsukamoto, Yuki Nakamura, Shu Nakaharai, Takuya Iwasaki, Kenji Watanabe, Takashi Taniguchi, Shinichi Ogawa, Yukinori Morita, Kento Sasaki, Kensuke Kobayashi. 2024-11-16. Systematic characterization of nanoscale $h$-BN quantum sensor spots created by helium-ion microscopy. https://doi.org/10.1103/physrevapplied.22.054026

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