Dr. Louise Bradley

Prof. Bradley leads a vibrant research team in the field of photonics, with current research interests mainly in the area of nanophotonics. Her research is directly relevant for development of higher efficiency light emitting devices, solar cells and sensing applications. She has previously made significant contributions to the development of novel devices for optical telecommunications systems. In 1992 she received a BSc (First Class Hons.) in Experimental Physics from University College Dublin. She was awarded Forbairt and Trinity College Dublin scholarships to pursue postgraduate studies at Trinity College Dublin, obtaining a MSc in 1994 and a PhD in 1998. During her PhD she studied nonlinear optical processes in semiconductor microcavity systems. As a Postdoctoral Research Fellow she worked on the development of semiconductor microcavity devices for lighting applications. In 1999, she became a Lecturer in the Institute of Technology, Tallaght, before returning to join the academic staff of the School of Physics in 2000. Subsequently, she was appointed Senior Lecturer and elected to Fellowship of the College in 2009, and promoted to Professor in 2016. Dr. Bradley has won over 3.55 M€ in competitive funding from Science Foundation Ireland, Enterprise Ireland and the Irish Research Council. She has published over 140 scientific papers and collaborates with national and international research teams.

  CAVITY POLARITONS   Condensed matter, optical and dielectric properties   FABRICATION   Laser technology   NANOSTRUCTURES   Nanotechnology   Nonlinear Dynamics   Optical materials   Optics   PHOTOLUMINESCENCE   Photon Science & Technology   Photonic Networks   Photonics   Physics   QUANTUM-WELL   SEMICONDUCTOR DEVICES AND MATERIALS   SEMICONDUCTOR LASERS   SEMICONDUCTOR NANOCRYSTALS   SEMICONDUCTOR OPTICAL AMPLIFIERS   Semiconductor optoelectronics   SEMICONDUCTOR QUANTUM WELLS   SEMICONDUCTOR-LASERS   SEMICONDUCTORS   SPECTROSCOPIC CHARACTERIZATION   Telecommunications Research

My current research interests include nanophotonics and plasmonics for novel functionality and enhanced performance of photonic devices. A key direction of my research is investigation of near-field energy transfer in semiconductor systems. Of fundamental importance for energy transport and control of interactions between quantum emitters on the nanoscale, this process has far-reaching consequences for sensing, optical computing, light emitting devices and light harvesting applications. My research over the past few years has concentrated plasmonic coupled systems, including enhanced non-radiative energy transfer and emission. My group was the first to report experimental plasmonic enhancement of energy transfer between quantum dots. Subsequently, I published a number of papers demonstrating the role of different parameters in controlling the energy transfer signatures. Most recently, my group has demonstrated that plasmon-enhanced energy transfer can be applied in hybrid material systems which are technologically of great interest, We have reported on plasmon enhanced energy transfer between InGaN quantum wells and quantum dots which can be used for improved light emission and light-harvesting devices. My group is also currently investigating plasmon coupled chiral systems, QD- 2D (MoS2) materials and plasmon-graphene structures. Leading groups in state of the art colloidal QD and plasmonic nanocrystals (Gaponik (TU Dresden), Rogach (City University, Hong Kong and Gun'ko (Chemistry, TCD)), have provided materials for my research over many years. Other collaborators include Prof. Parbrook from the Tyndall Institute, Cork who is an expert in the growth of GaN materials. Tailored plasmonic structures are fabricated using focused-ion beam, e-beam lithography and helium-ion lithography. Interaction with nanoscale metallic features can result in modified emission properties, in terms of intensity, directionality and polarization. Plasmonic structures can facilitate improved performance and enhanced functionality for many applications including, but not limited to, light emitting devices, light harvesting, sensing, quantum optics and all-optical data processing. We have developed a wide range of characterization techniques for the investigation of these nanoscale systems. Over my career I have developed a broad expertise in the field of photonics. My earlier work concentrated on semiconductor microcavity physics and devices. During my PhD I used dynamic non-linear techniques, such as pump-probe and four-wave-mixing, to study the physics of cavity polaritons in semiconductor microcavities. Following on from this work, I investigated how microcavities could be used to enhance non-linear processes, in particular for microcavity-enhanced two-photon absorption based detector. Microcavity structures can also be used to enhance and direct emission. I participated in the EU framework project, AGETHA, with responsibility for the optical design of GaN-based microcavity light emitting devices. I applied my knowledge of pump-probe systems for the development a contra-propagation pump-probe technique for the study of the polarization dependence of intra-band carrier dynamics in semiconductor optical amplifiers and the influence of these dynamics on nonlinear polarization rotation. This project, in collaboration with Dr. P.Landais (DCU), was interested in the potential of nonlinear polarization for optical switching. The collaboration led to a further successful project which demonstrated the lowest noise-figure to date for a bulk SOA using novel a multi-contact structure to control the carrier distribution along the length of the device.