A Fully‐Integrated Diamond Nitrogen‐Vacancy Magnetometer with Nanotesla Sensitivity

Abstract

Ensemble diamond nitrogen‐vacancy (DNV) centers have emerged as a promising platform for precise earth‐field vector magnetic sensing, particularly in applications that require high mobility. Nevertheless, integrating all control utilities into a compact form has proven challenging, thus far limiting the sensitivity of mobile DNV magnetometers to the ‐level. This study introduces a fully integrated DNV magnetometer that encompasses all the essential components typically found in traditional platforms, while maintaining compact dimensions of approximately 13 cm 26 cm. In contrast to previous efforts, these challenges are successfully addressed by integrating a high‐power laser, a lock‐in amplifier, and a digitally‐modulated microwave source. These home‐made components show comparable performance with commercial devices under the circumstance, resulting in an optimal sensitivity approaching 2.14 nT ()−1. The limitations in this system as well as possible future improvements are discussed. This work paves the way for the use of DNV magnetometry in cost‐effective, mobile unmanned aerial vehicles, facilitating a wide range of practical applications.