Solid-state cavity quantum electrodynamics with spin ensembles

Abstract

Quantum sensors have the potential to operate at fundamental physical performance limits. Among various quantum sensing platforms, solid-state spin emitters stand out due to advantageous characteristics such as room-temperature spin polarization and readout, atomic-scale spatial resolution, and extended coherence times. Despite these strengths, traditional optical detection methods exhibit low readout fidelity in solid-state ensembles, severely limiting their achievable sensitivity. This thesis addresses this limitation by coupling a solid-state emitter ensemble to a microwave cavity, forming a cavity quantum electrodynamics system. Our approach eliminates the need for photon collection required by conventional optical readout methods, and the resulting strongly coupled system allows efficient cavity-based probing of the solid-state spin ensemble. By exploiting the hybrid quantum system with cavity quantum electrodynamics, we achieve record-high sensitivity for solid-state quantum sensors, representing a substantial advancement toward achieving fundamental sensing limits.