Radio Frequency Precession Modulation-Based Magnetic Field Sensors

High sensitivity is often the foremost characteristic for magnetic field sensors; however, the most sensitive systems tend to be attributed with being any combination of large in size, high in power consumption, complex in design, or exorbitant in cost. This fact not only limits accessibility to the technology afforded by high sensitivity sensing, but it also restricts the extent to which potential applications of magnetic field sensing may be realized. Herein we propose a concept for sensor operation that can achieve sensitivities competitive with those of modern magnetic field sensors while simultaneously maintaining small size, low power consumption, simplicity in design, and low cost. This is accomplished through employment of the nonlinear precession dynamics of electron spins to attain parametric amplification of a magnetic field. A preliminary experimental implementation of the proposed concept establishes its feasibility and is already able to demonstrate benefits over existing approaches to sensing. The implementation exhibits a sensitivity of 23.2 pT/Hz1/2 with a volume of 0.0564 mm3 and a power consumption of -40.96 dBm.