Nonlinear Plasmon, Rayleigh Scattering and Terahertz Dynamics in Phase-Change Correlated Oxides
Abstract
This research program focuses on new and deeper understanding of fundamental processes in ultrafast light-induced insulator-to-metal and metal-to-insulator phase transition (PT) dynamics in correlated vanadium oxides, and intends to elucidate the evolution of nonequilibrium phases upon photoexcitation. The project will be conducted by Prof. Sergiy Lysenko (principal investigator, PI) in collaboration with Prof. Félix Fernández (key person). Methods of femtosecond spectroscopy will help to separate the charge and lattice dynamics upon PT and to provide direct observation of the evolution of electronic and structural material properties. The research effort is organized into three separate thrust areas: (1) synthesis of phase-change vanadium oxide thin films, and multilayer/plasmonic structures; (2) time-resolved light scattering and plasmon spectroscopy of photoexcited vanadium oxides; (3) time-domain terahertz spectroscopy. Special effort will be made to monitor nonlinear optical response of the materials during the ultrafast PT versus size and statistical distribution of grains, single nanoparticles and domains. The scientific and technical merit of the project resides in (i) observation and understanding the role of electronic correlations in photoexcited state dynamics, and how the PT dynamics in vanadium oxides depends on size of particles/grains in thin solid films, stoichiometry and structural disorder of materials; (ii) knowledge to be gained about critical parameters controlling the light-induced phase transition dynamics (laser fluence threshold level for the phase transition, stoichiometry and structural disorder); (iii) knowledge about surface plasmon-polariton dynamics in vanadium oxides and its role in the PT process. (iv) In order to answer fundamental questions about the nature and behavior of excited electronic states novel angle-resolved ultrafast light scattering and THz spectroscopy methods will be used. This project will provide a development and enhancement of new research capabilities at the University of Puerto Rico-Mayaguez (UPRM). State-of-the-art THz time-domain spectroscopy system and high-resolution ultrafast light scattering optical setup to monitor surface plasmon-polariton scattering will be assembled in the lab. These setups will be combined with a femtosecond laser system available in our lab and will greatly enhance the research capabilities without the need to acquire new major equipment. The THz spectroscopy setup will be the first ultrafast terahertz source in Puerto Rico for studies of solid state materials and will have many applications beyond the project described here. Sophisticated compressors of ultrafast optical pulses will be assembled to be employed for visible and near-infra-red spectral region. The project will provide an excellent educational and training opportunity in ultrafast spectroscopy for graduate and undergraduate students at UPRM. One undergraduate and two graduate students per year will be directly supported by the project. Also one postdoctoral researcher will be trained in order to establish state-of-the-art research capabilities in ultrafast nonlinear optics and condensed matter physics at UPRM.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 11, 2016
- Source ID
- W911NF1510448
Entities
People
- Sergiy Lysenko
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- University of Puerto Rico at Mayaguez