A chip-integrated ultralow-noise photoelectrically detected NV magnetic resonance sensors

We demonstrated a chip-integrated diamond quantum sensor with a wide-bandwidth, low-noise, high-gain transimpedance amplifier (TIA), operating on the principle of photoelectrically detected2 magnetic resonance (PDMR). The TIA operates close to its fundamental noise limits, and the3 whole system exhibits a clear dispersive lock-in response under microwave frequency modulation at rates of up to 280 kHz for sub-picoampere PDMR currents. The integrated TIA architecture further enables detection of PDMR signals from one or two independent pixels and opens the way to multiplexed detection, with individual pixels controlled by switching their bias voltage. Magnetic field sensitivity of 166 nT/√Hz was demonstrated, with a theoretical limit of 200 pT/√Hz. These results demonstrate the feasibility of fast, scalable PDMR readout and represent an important step toward high-resolution, chip-scale, multi-pixel magnetic-field imaging based on NV centers in diamond.