Reginald Wilcox—A Solid-State Ruby Magnetometer

Reginald Wilcox, a PhD Candidate in MIT's Department of Electrical Engineering & Computer Science and a Research Assistant at MIT Lincoln Laboratory, delivered the Nano Explorations talk on September 13, 2022. Quantum sensors offer the potential for dramatic enhancements in sensitivity, accuracy, and size compared to their classical counterparts. In particular, solid-state spin-based quantum sensors have seen rapid development in recent years, with applications ranging from bio-medical imaging to magnetic mapping and navigation. Traditionally, these sensors have used optical methods to prepare and read out quantum states, which poses complications for reducing device size, power, and complexity, and limits sensing species to optically-polarizable defects. In this talk, Wilcox will demonstrate a fully non-optical solid-state quantum sensor architecture using chromium defects in sapphire. The novel state preparation technique harnesses thermal population imbalances induced by the defect's zero-field splitting. Readout is performed by extending the cavity-enhanced microwave technique recently demonstrated in NV diamond. The resulting magnetometer is broadband with a minimum sensitivity of 9.7 pT/sqrt(Hz) near 5 kHz and a compact sensing head. Future improvements could include enhanced sensitivity from cavity frequency-locking and expansion to full vector magnetometry. -------------------------------------------------------- Nano Explorations is a virtual seminar series powered by MIT.nano that features presentations by MIT students and postdocs on their work in nanoscience, nanotechnology, and other advanced research fields. The series was launched as a way to keep our nano community connected during the COVID-19 pandemic. Presentations take place once a month and are open to any interested viewers. Read more about past and upcoming Nano Explorations at mitnano.mit.edu/nano-explorations.