Optically Detected Magnetic Resonance of NV- Centers in Diamond.

Optically Detected Magnetic Resonance (ODMR) based on nitrogen-vacancy (NV) centers in diamond has emerged as a powerful quantum sensing technique owing to its exceptional sensitivity to magnetic, electric, and thermal fields. The development of compact and portable ODMR-based platforms offers promising opportunities for next-generation sensing applications across diverse environments. In this work, we present both theoretical modeling and experimental demonstration of ODMR spectra using a controllable radio-frequency (RF) source and custom-built antenna integrated with a solenoid. The tunable RF control enables precise manipulation of resonance conditions, allowing systematic investigation of the ODMR dip characteristics. These results provide essential insights toward the design and realization of a portable, electron-spin–based quantum sensor for practical field-deployable applications.