Excited-State Optically Detected Magnetic Resonance of Spin Defects in Hexagonal Boron Nitride

Negatively charged boron vacancy (V-B(-)) centers in hexagonal boron nitride (h-BN) are promising spin defects in a van der Weals crystal. Understanding the spin properties of the excited state (ES) is critical for realizing dynamic nuclear polarization. Here, we report zero-field splitting in the ES of D-ES = 2160 MHz and its associated optically detected magnetic resonance (ODMR) contrast of 12% at cryogenic temperature. In contrast to nitrogen vacancy (NV-) centers in diamond, the ODMR contrast of V-B(-) centers is more prominent at cryotemperature than at room temperature. The ES has a g factor similar to the ground state. The ES photodynamics is further elucidated by measuring the level anticrossing of the V-B(-) defects under varying external magnetic fields. Our results provide important information for utilizing the spin defects of h-BN in quantum technology.

Automated summary

This study reports the spin properties of the excited state of negatively charged boron vacancy centers in hexagonal boron nitride. The results provide important information for realizing dynamic nuclear polarization and utilizing these spin defects in quantum technology.