Parametric Amplification in Depletion Layer Transduced Microelectromechanical Resonator

This paper introduces a method for signal amplification and enhancement of full width half maxima (FWHM) in a depletion layer-transduced flexural resonator using the parametric effect. The device can be used as a filter-amplifier, or as a low-noise readout method for sensors. Parametric excitation shows a significant drop in device impedance, from 334.2 k<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> without a pump signal to 45.9 k<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> with a 300 mV pump signal. In the absence of the pump signal, with an input power of −10 dBm, the resonator produces an output power of −44.87 dBm at ~400 kHz and a FWHM value of 23 Hz. However, when a 200 mV pump signal at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2f_{0}$ </tex-math></inline-formula> with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi $ </tex-math></inline-formula>/2 phase shift, is superimposed with the same input power, the resonator’s output power amplifies to −11.49 dBm, and the FWHM value substantially decreases to 10 Hz. This leads to a 33.58 dBm of amplification and 2.3x improvement in Q attributed to the parametric effect. A detailed analytical model of the transducer is presented. [2024-0061]