Spin property improvement of boron vacancy defect in hexagonal boron nitride by thermal treatment

Abstract

Abstract Negatively charged boron vacancy (V B –) in hexagonal boron nitride has attracted attention as a promising spin defect for quantum sensing applications. Hence, a fabrication method for generation of V B – with superior spin properties would be desirable. In this study, we demonstrated V B – formation by two thermal treatment methods. Both methods improve the signal-to-noise ratio of optically detected magnetic resonance signal by a factor of 4. Furthermore, a zero-field splitting parameter E which reflects crystal distortion after irradiation significantly reduces for irradiation above 650 °C. These findings indicate that thermal treatment is an effective method for a V B – based quantum sensor.