QUANTCAD LLC — National Aeronautics and Space Administration SBIR Phase I: S16

Description

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 purifiedand 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 nanosats or picosats as their size, power, and complexity restrictions are most severe.nbsp;Microscopic modeling of the spin-dependent dynamics in SiC-based all-electrical devices will confirm the extreme sensitivity to magnetic fields in isotopically purified SiC. Device simulations of the macroscopic electrical device surrounding this spin-dynamical active region will determine optimal band alignment, electric field distribution, and carrier density profiles. We will design the optimal sensitivity of the magnetometer based on tradeoffs for isotopic purity, regularity of thickness of dielectric and defect occurrence. A Phase II plan will be constructed, identifying the issues related to device growth and fabrication, testing approaches for the near-zero-field magnetoresistance, and integration into magnetometers. Plans will be developed to mitigate issues and partners confirmed for the Phase II project.nbsp;