Tuneable Dual-Mode Micro-Resonator Associating Photonic Crystal Membrane and Fabry–Perot Cavity

We report on a tuneable dual-wavelength micro-resonator with a resonant photonic crystal membrane (PCM) inserted in a vertical Fabry-Perot (FP) cavity. Strong optical coupling between both resonators leads to dual-wavelength resonances. Their energy difference, determined by the overlap of both modes, can be tuned using micro-opto-electro-mechanical systems. Variations in spectral and field overlaps are considered separately with a phenomenological matrix method through, respectively, the FP cavity thickness and the PCM position change. This approach is compared with 2-D finite-difference time-domain simulations in the second case. Periodic evolution of both modes is observed with unsymmetrical amplitude, unlike with the model cause of its approximations.