Spin Relaxometry with Solid-State Defects: Theory, Platforms, and Applications

• URL: http://arxiv.org/abs/2602.01521v1
• Date: Mon, 02 Feb 2026 01:27:59 GMT
• Title: Spin Relaxometry with Solid-State Defects: Theory, Platforms, and Applications
• Abstract summary: Review bridges theory and experiment, clarifying how measured relaxation rates map onto noise spectra.<n>We highlight applications across condensed-matter physics, chemical and biological sensing, and relaxometry-based magnetic-resonance spectroscopy.
• Score: 10.921609803217828
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Spin relaxometry using solid-state spin defects, such as the diamond nitrogen-vacancy (NV) center, probes dynamical processes by measuring how environmental fluctuations enhance the spin relaxation rate. In the weak-coupling limit, relaxation rates sample the transverse magnetic-noise power spectral density through a sensor-specific filter function, turning the defect into a local, frequency-selective noise spectrometer. This review bridges theory and experiment, clarifying how measured relaxation rates map onto noise spectra and how near-field geometry shapes the response. We highlight representative applications across condensed-matter physics, chemical and biological sensing, and relaxometry-based magnetic-resonance spectroscopy. We conclude with emerging opportunities and key challenges.

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