Design and modeling of stable, high Q-factor curved Fabry-Pérot cavities

In this paper, we introduce a novel design for high performance silicon-based Fabry-Pérot cavities and its corresponding design model. According to the design model, the new design shows higher stability, lower insertion losses and higher quality factor. Our methodology was based on one hand, on taking advantage of light reflection and refraction over curved surfaces with curvatures along 2 orthogonal directions, in order to confine the Gaussian beam inside the cavity, thus reducing diffraction loss. Such design enables approaching new limits, where Q-factor is governed mainly by the mirrors reflectivity. On the other hand, the use of Bragg reflectors, obtained by DRIE etching enables reaching reflectivities above 99%, thus enabling very high Q-factors.