Our main scientific interest is nanophotonics and in particular the coherent interaction of light with mesoscopic and nanoscale complex photonic systems.
Our research activity is focussed on single-emitter spectroscopy, mainly in complex nanophotonic systems in the form of photonic networks. We are trying to understand how extended and localised light modes can be exploited to route . When many light emitters are coupled collective effects such as stimulated emission can be triggered and lasing can be achieved.
Single emitter NANOSCALE spectroscopy
Nanophotonics and nanoscale optics, which are aimed at coherent control and manipulation of single photons emitted by individual quantum emitters in a nanostructured photonic environment offer a revolutionary new approach to computation and information technology: bits can be carried in the state of light and processed by nanoscopic amount of matter.
MODAL COUPLING OF SINGLE PHOTON EMITTERS WITHIN NANOFIBRE WAVEGUIDES
We have shown that soft-matter nanofibers can channel individual photons into fibre modes that can transport them at distant locations, for example on a chip. These nanofibers do not rely on resonant interactions, making them ideal for room-temperature operation, and offer a scalable platform for future quantum information technology. Link to the paper.
COMPLEX PHOTONIC NETWORKS
Complex nanophotonic networks offer a unique approach to light transport and light emission control, by designing a set of distributed single emitters that share information through photonic connections, and that can be remotely addressed. Moreover the unique scattering properties of a network naturally allow for designed recurrent scattering.
INDIVIDUAL QUANTUM DOTS IN A RANDOM PHOTONIC NETWORK
Each appearing and disappearing white spot is a quantum dot blinking, encapsulated in a network of subwavelength optical fibres.
HYPERUNIFORM DISORDERED NETWORKS
Hyperuniform disordered photonic materials are a new class of materials that harness structural disorder and control light transport, emission and absorption in unique ways, beyond the constraints imposed by conventional photonic microcircuit architectures. Hyperuniform materials are statistically isotropic and possess a constrained randomness such that density fluctuations on large scales behave more like those of ordered solids, crystals or quasicrystals, rather than those of conventional amorphous materials.
Together with Marian Florescu (Surrey University) we are studying hyperuniform disordered nanophotonic structures in which geometrical and topological correlations can enable next-generation photonic devices, including low-threshold micro-lasers and novel flexible optical micro-circuit platforms for future optical IT.
Unconventional and random lasing
Lasers are directional and monochromatic sources of radiation. Contrary to common beliefs none of these properties are key to a laser, as the only requirement is that the radiation is originated by stimulated emission instead of spontaneous emission as an ordinary lamp. Stimulation is a complicate process that requires light trapping in the optical gain (for amplification). Disordered media can trap light via multiple scattering and can become the unconventional source of laser light, in the form of random lasing.
BIOCOMPATIBLE RANDOM LASING
Random lasing, where light amplification and lasing emerge from light trapped in a disordered matrix, naturally has a biocompatible porous form, is as small as ~10 μm, and can become the ideal candidate for integration with living tissues. With this goal in mind we have developed a natural silk disordered matrix capable of lasing. Link to the paper, and pdf.
We have also developed a diffusive dispersive model of random lasing, we are happy to share the code if you are interested. Link to the paper, and pdf.