<title>Photonic all-silicon microsensor for electromagnetic power in the microwave and millimeter-wave range</title>

Abstract

A new type ofnon-perturbing electromagnetic power sensorfor microwaves and millimeter-waves, based on the thermooptical effect in a silicon interferometric etalon cavity, is presented. The incidentfieldpower is partially dissipated into the all-silicon metal-less etalon, constituting the sensing element of the detector, so causing its temperature increase. This, in turn, induces the intensity modulation of a probe laser beam reflected by the cavity after a multiple beam interference process. The sensing element is directly connected to an optical fiber for remote interrogation, so avoiding the use of perturbing coaxial cables.The performances ofsuch a new class ofnon-perturbing and widebandprobes, in terms ofsensitivity and resolution are discussed in detail. The experimental results concerning the characterization of a preliminary prototype sensor are presented and compared with theoretical data. The dependence of the sensor response on the electromagnetic frequency and on the sensing element characteristics isfinally discussed.