Abstract
We report on enhancements in the gain of silicon nitride (SiNx) nanomechanical resonators by parametric amplification using a dielectric gradient force pumping. With this technique, high mechanical quality factors (Q) of over 20,000 at resonant frequency of 6.79 MHz are achieved even at room temperature. By applying a constant electric bias voltage (Vdc), we show the resonant frequency to be dependent on static tension. To periodically modulate the spring constant of the resonator, a parametric pumping signal twice its resonant frequency (2f0) is applied simultaneously with the Vdc, and at room temperature, the phase-sensitive parametric gain is 9.62.