Our nano-optics research focusses on the control of light-matter interactions at the nanoscale. We investigate the interaction of light with nano-structures such as inorganic semiconductor quantum dots (QDs), tailoring the interaction through control of the QD’s photonic environment. This is achieved by embedding QDs in optical waveguides and cavities (waveguide and cavity QED, respectively). A key goal of waveguide QED is to realise a ‘1 dimensional atom’ – a QD coupled only to a single optical waveguide mode, and therefore exhibiting strong interactions with single photons. Similarly, cavity QED can be used to significantly enhance the QD-photon coupling strength, resulting in phenomena such as the Purcell effect and strong coupling.
This research activity is funded by our EPSRC Programme Grant ‘Semiconductor Quantum Photonics: Control of Spin, Exciton and Photon Interactions by Nano-Photonic Design’. As part of this programme, we are investigating the generation of single photons by QDs, and their integration with miniature photonic circuits on semiconductor chips. We are also investigating the use of resonant lasers to perform coherent quantum control experiments of individual exciton and spin states in QDs. By combining these two techniques, our goal is to interface static qubits (exciton or spin states in QDs) with flying qubits (photons), in order to demonstrate the key components of quantum networks.