  Nanoelectromechanical resonators have been successfully used for a variety of
sensing applications. Their extreme resolution comes from their small size at
the cost of low capture area, making the "needle in a haystack" issue acute.
This leads to poor instrument sensitivity and long analysis time. Moreover,
electrical transductions are limited in frequency, which limits the achievable
mechanical bandwidth again limiting throughput. Multiplexing a large number of
high-frequency resonators appears as a solution, but this is complex with
electrical transductions. We propose here a route to solve these issues, with a
multiplexing scheme for very high frequency optomechanical resonators. We
demonstrate the simultaneous frequency measurement of three silicon microdisks
resonators fabricated through a Very Large Scale Integration process. The
readout architecture is simple and does not degrade the sensing resolutions.
This paves the way towards the realization of sensors for multi-parametric
analysis, extremely low limit of detection and response time.
