Wide-field NV magnetometry under simultaneous high-pressure and high-temperature conditions

Masahiro Ohkuma; Eikichi Kimura; Shumpei Ohyama; Miu Tezuka; Ryo Matsumoto; Shinobu Onoda; Yoshihiko Takano; Shintaro Azuma; Kenji Ohta; Keigo Arai

arXiv · 2606.25378

Wide-field NV magnetometry under simultaneous high-pressure and high-temperature conditions

Masahiro Ohkuma·Eikichi Kimura·Shumpei Ohyama·Miu Tezuka·Ryo Matsumoto·Shinobu Onoda·Yoshihiko Takano·Shintaro Azuma·Kenji Ohta·Keigo Arai

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Abstract

We demonstrate wide-field optically detected magnetic resonance (ODMR) under simultaneous high-pressure and high-temperature conditions using nitrogen-vacancy (NV) centers. Although NV-center magnetometry has been widely used for spatially resolved magnetic-field imaging, its application to extreme environments combining pressure and temperature remains challenging. In this work, we show that ODMR can be observed at 5 GPa and 500 K, demonstrating the feasibility of NV spin readout under such combined extreme conditions. We further perform wide-field ODMR of iron at 7 GPa and 500 K, where the stray magnetic field from the sample is spatially visualized through the pressure cell. These results establish NV-center magnetometry as a promising platform for imaging magnetic phenomena in materials under high-pressure and high-temperature environments.

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Masahiro Ohkuma, Eikichi Kimura, Shumpei Ohyama, Miu Tezuka, Ryo Matsumoto, Shinobu Onoda, Yoshihiko Takano, Shintaro Azuma, Kenji Ohta, Keigo Arai. 2026-06-24. Wide-field NV magnetometry under simultaneous high-pressure and high-temperature conditions. https://arxiv.org/abs/2606.25378

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