Fiber-Coupled Absorption-based Quantum Sensing with Nitrogen Vacancy Ensembles in a Suspended Diamond Photonic Cavity

Low photon extraction efficiency limits the optical spin readout fidelity in emerging quantum sensing technologies in diamond. Here, we propose and fabricate integrated diamond nanoprobes based on cavity-enhanced IR absorption of embedded Nitrogen Vacancy centers. The design allows for near-unity readout fidelity, enables high spatial resolution and massively parallel detection schemes.