Princeton’s Multiplexed Diamond Magnetometer

Massively Multiplexed Nanoscale Magnetometry with Diamond Quantum Sensors

Researchers from Princeton University have developed a massively multiplexed quantum sensing platform using nitrogen vacancy (NV) centers in diamond, as detailed in Physical Review X. These NV centers are atomic-scale defects that can detect magnetic fields with high sensitivity.

Traditionally, NV centers are measured one at a time using confocal microscopy, which limits scalability and throughput. This study introduces a new method that allows hundreds of NV centers to be read simultaneously using a low-noise camera and a spatial light modulator (SLM).

The team used two Cobolt lasers in the study: the Cobolt 06-MLD 520 nm green laser was used to optically detected magnetic resonance (ODMR) measurements of all the NV centers in the field of view; while the Cobolt Mambo 594 nm orange laser enabled multiplexed spin-to-charge conversion (SCC), which significantly reduced readout noise and improved fidelity (up to 88%). This was essential for measuring magnetic field correlations (covariance magnetometry) across multiple NV centers.

The new high-fidelity readout platform can be applied in the study of condensed matter phenomena that are characterized by the noise spectrum or correlation functions.