High-Sensitivity Isotopically-Purified All-Electrical Chip-Scale Atomic Magnetometers

All-electrical chip-scale atomic magnetometers based on spin-coherent transport effects through atomistic defects in semiconductors will have orders of magnitude improved sensitivity if the semiconductor hosts are isotopically purified and related device parameters optimized. Current all-electrical chip-scale atomic magnetometers have room-temperature sensitivities ~400 nT/root-Hz, and the proposed innovation we estimate conservatively to provide room-temperature sensitivities of 400 pT/root-Hz with possibilities as low as 100 pT/root-Hz. These are comparable to those achievable with NV-diamond chip-scale atomic magnetometers, but without the requirement for microwave fields or optical elements. These small-scale magnetometers would avoid the need to self-calibrate, compared to fluxgate magnetometers, and avoid challenges related to diffusion of gas through a glass cell and radiation damage of fiberoptics. They would thus be very well suited for NASA missions and nanosats as their size, power, and complexity restrictions are most severe.nbsp;In Phase II we plan to build a bench-top prototype based on microscopic- and device-level models of the spin-dependent dynamics in SiC-based all-electrical magnetometer developed in Phase I. Our Phase I results confirmed the dramatically improved sensitivity to magnetic fields in isotopically purified SiC. We will work with our partners to conduct further device design, epilayer growth, device fabrication and characterization in an iterative development cycle that will culminate in the second year where our objective is to demonstrate a magnetometer prototype that meets the targeted device performance in NASA-relevant environments as assessed by JPLrsquo;s mu-house facility.