Integrated microresonator based quantum optics

Our group is investigating the uses of silicon chip based optical microresonators in the areas of quantum optics and quantum information. Microresonators enable many of the key components of a quantum computer including quantum gates, quantum memories, and quantum resource generation. In our group we work with microtoroidal resonators, which were first developed in 2003 in the Vahala group at Caltech. These resonators exhibit the ultra-strong optical confinement required for microresonator based quantum gates and non-classical state generation, in an integrated architecture naturally suited for the implementation of large scale systems. We are investigating the generation of in fiber entangled optical fields using the Kerr non-linearity in microtoroids, with the goal of using this entanglement to perform new tests of non-locality in quantum mechanics.

Integrated microresonator based quantum-optomechanics

Quantum opto-mechanics is a new area, where radiation pressure couples mechanical and optical degrees of freedom at the quantum level. There is currently a big international push to utilise this coupling to achieve cooling of a mechanical resonator down to its quantum mechanical ground state. Ground-state cooled mechanical resonators would open the new area of quantum mechanics, that is to say, it would drive truely mechanical systems into a regime where quantum mechanics is required to understand their behaviour. This could not only further our understanding of the physical world, but also allow new technologies such as ultra-sensitive mass or spin sensors capable of detecting single atoms, or memories for quantum computers. Microtoroidal resonators are a natural quantum opto-mechanical system, inherently combining both high quality mechanical and optical resonators, and have been pioneered in this area recently by the Kippenberg group at MPQ. We have a new research programme in this area looking at utilising opto-mechanical coupling for the generation of non-classical optical and mechanical states.

Biophotonics applications of quantum technology

Over the past two decades many highly sophisticated experimental techniques have been developed within the quantum optics and quantum information communities. Our group is focussed on transferring those techniques to other fields, and in particular to biophotonics. Biophotonics incorporates all forms of interaction between biological and optical systems, including both the observation and manipulation of cells and molecules, and the use of biomolecules for non-linear optics and lasers. In our work we focus specifically on utilising microtoroidal resonators for biological sensing; and on optimal implementations of optical tweezers for spatial manipulation of molecules, and ultra-precise force measurement.