Cavity optomechanics with hybrid mirrors
I analysed hybrid optomechanical systems formed by dielectric membranes doped with two-level quantum emitters or patterned with photonic crystal structures. Such hybrid mirrors strongly reflect light around a particular wavelength, leading to a modified response to light. My goal was to find out what interesting applications such devices might have. Some existing optomechanical experiments—such as optomechanical cooling—can be improved with this approach.
Mechanical oscillators can couple to a broad range of external forces and are thus suitable for conversion of signals between different carriers. One particular—and important—example is the conversion between microwaves and light which can be used improve detection of weak microwave signals or for conversion of quantum signals between superconducting quantum computers (operating at microwave frequencies) and light (suitable for long-distance quantum communication).
Gaussian entanglement of light
Gaussian states of light are an important subclass of all quantum states of light owing to their easy creation and manipulation. Most importantly, entangled Gaussian states can be prepared deterministically, unlike entangled states based on single photons. An important topic of research is finding states best suited for a specific task (such as quantum teleportation) or developing efficient protocols involving non-Gaussian operations (which are necessary, for instance, for entanglement concentration and distillation).