2D quantum sensor uses spin defects for precise magnetic field detection

Researchers at the University of Cambridge have unveiled a significant advancement in quantum sensing by utilizing spin defects in hexagonal boron nitride (hBN) to detect magnetic fields at the nanoscale with high precision. This innovation operates effectively at room temperature and offers a multi-axis sensing capability, distinguishing it from traditional single-axis sensors.

Quantum sensors are instrumental in detecting minute variations in physical quantities. In magnetometry, they enable visualization of properties like current flow and magnetization at the nanoscale, facilitating the discovery of new physical phenomena and functionalities. Dr. Carmem Gilardoni, co-first author of the study, emphasized that this work enhances such capabilities by leveraging hBN, a material compatible with nanoscale applications and offering new degrees of freedom compared to existing nanoscale quantum sensors.

Traditionally, nanoscale quantum magnetometry at ambient conditions has relied on nitrogen vacancy (NV) centers in diamond. While effective, NV centers are limited by their single-axis detection and constrained dynamic range. In contrast, the hBN-based sensor developed by the Cambridge team exhibits multi-axis magnetic field detection with a broader dynamic range.

The researchers discovered that the sensor’s enhanced performance stems from the low symmetry of the hBN defects and their favorable excited state optical rates. These characteristics contribute to the sensor’s robust and versatile magnetic field detection capabilities.