Optomechanics is the field devoted to the study of interactions between optical and mechanical degrees of freedom. This field emerged in the mid-1990s in the context of the study of the fundamental processes involved in interferometric measurements, and their implications for the detection of gravitational waves. This booming field is, even today, mainly focused on the measurement of macroscopic mechanical resonators with a precision reaching the quantum limit. However, This coupling is enhanced at the nano-scale because of the very small mass of nano-mechanical resonator.
Thus, at the Center fo Nanosciences and Nanotechnologies, I’m investigating optomechanics on suspended photonic crystal membranes, the optical analogue of electrons in condensed matter.
Depending on the arrangement of holes, the membrane can either act as a deformable end-mirror in a conventional Fabry-Perot cavity or include a cavity of diffraction-limited volume that simultaneously confines both phonons (i.e. mechanical vibrations) and photons. These structures combine cavity enhancement and low mass and thus exhibit strong mechanical coupling to light. In particular, optomechanical resonators formed by conventional photonic crystal membranes sustain mechanical modes ranging from the MHz to the GHz frequency.
Depending on the configuration, photonic crystal membranes developed at C2N, allows studying nonlinear dynamics of single and coupled opto-electromechanical resonators, reaching microwave optomechanical oscillators and also temperature metrology.