Bridging Mid- and Near-Infrared by Combining Optomechanics and Self-Mixing

This work describes a self-mixing-assisted optomechanical platform for transferring information between near- and mid-infrared radiation. In particular, the self-mixing signal of a mid-infrared quantum cascade laser is used to detect the oscillation of a membrane driven by light-induced forces exerted by a near-infrared excitation beam, which is amplitude-modulated at the membrane resonance frequency. This technique benefits from spectral broadness and, therefore, can link different spectral regions from both the excitation and the probe sides. This versatility can pave the way for future applications of this self-mixing-assisted optomechanical platform in free-space communication and advanced sensing systems.