Proposal to resurrect femtosecond laser labs for probing electronic materials

点击翻译按钮获取中文摘要

The requested instruments form an enabling role in our comprehensive integrated system for investigating charge carrier dynamics in optoelectronic materials. The Kambhampati group are world experts at femtosecond laser spectroscopy. The objective of femtosecond laser spectroscopy is to resolve in time the primary dynamical events in some chemical or physical process. In our group we focus on charge carrier dynamics in semiconductor nanostructures such as semiconductor quantum dots and semiconductor perovskites. Both materials are central to the emergence of materials for our energy future. Both materials have an electronic response in which the materials are favorable for both light absorptive applications like photovoltaics and light emissive applications like LEDs. Hence one aims to perform femtosecond laser spectroscopy in the electronic regime to be able to probe carrier dynamics. In our group we have a suite of three world class ultrafast spectrometers distributed between two femtosecond laser labs. In our first lab commissioned in 2005 we have a home-built pump/probe spectrometer. And in our second lab commissioned in 2015 we have a home-built two-dimensional electronic spectrometer (2DE) and a time-resolved photoluminescence (t-PL) spectrometer. Each of our three instruments represents the state-of-the-art in femtosecond spectroscopy in the electronic regime. But the instrumentation is aging and needs new components and sub-systems to bring the spectrometers back to operational readiness. The spectrometer in Lab1 is nearly nonfunctional as the majority of the components are damaged due to aging and use. The spectrometer in Lab2 is functional but needs a few key improvements to keep it functioning research ready at the state-of-the-art. These integrated systems uniquely enable our research and training to proceed.      Without the requested tools our entire research program that is funded by NSERC, FQRNT, and Sony is decimated. 50% of our output comes from the pump/probe spectrometer in Lab1 which is totally dead. 25% of our output comes from the 2DE spectroscopy instrument in Lab2 and the t-PL instrument in Lab2. Right now only the t-PL instrument is working as intended. The 2DE instrument requires a new hollow core fiber light source, and a number of additional components to be research ready again. The pump/probe instrument has been down for a year now due to poorly functioning pump lasers. More importantly we have many optics and sub-systems that are malfunctioning whether electronically or optically.      With the requested funding, we will be able to continue to do our main line of research into producing breakthrough results on the dynamics of charges in materials for energy applications. These tools will enable our training of up to 10 HQP at the PHD level per year. The HQP will be trained at the highest levels of academic science, but also connection to industries.