Amplitude detecting micromechanical resonating beam magnetometer

摘要: A highly sensitive magnetometer is demonstrated using a resonant amplitude detection method in an integrated vacuum encapsulated microbeam which has very high quality factor (Q). The magnetic field efficiently converted to mechanical vibrations of the Q by Lorentz force between beam current and applied field. vibration causes optical modulation during transmission light through layers resonator. modulated produces electronic output signal at embedded photodiode just below microbeam. allows simple resonator structure good isolation from input leading less noisy output. Measured Q-values fabricated devices are above 50,000 with die yield exceeding 90%. sensitivities near 55,000 V/ATesla much higher than those reported for Hall effect devices.