2.5. Frequency measurements and IR spectroscopy
The sensor chip was mounted in an aluminium vacuum chamber providing electrical connection, a glass window for optical readout and a zinc selenide window for IR irradiation (Fig. 3 (2)). The resonators were actuated with an external piezoelectric element and read out with a laser-Doppler vibrometer (MSA-500, Polytec GmbH) mounted with a 632.8 nm helium neon readout laser. The nanomechanical