We report the successful detection of an audio signal via sideband modulation
of a nonlinear piezoelectric micromechanical resonator. The
270×96-μm resonator was shown to be reliable in audio detection for
sound intensity levels as low as ambient room noise and to have an unamplified
sensitivity of 23.9 μV/Pa. Such an approach may be adapted in acoustic
sensors and microphones for consumer electronics or medical equipment such as
hearing aids.Comment: 5 pages, 3 figure