Seminar: Structure and optical response of Si, Ge and SiGe nanoparticles produced by femtosecond laser printing approach

Date: June 26th
Time: 15.00-16.30

Speaker: Denis Zhigunov, senior research scientist at MSU
Bio: In 2003, Denis Zhigunov graduated from M.V. Lomonosov Moscow State University, Faculty of Physics, where he performed subsequently his PhD studies devoted to photoluminescence properties of erbium ions in silicon-germanium solid solutions and structures with silicon nanocrystals. He obtained his PhD degree in 2006, and continued his work as a research scientist at MSU. His responsibility included both research and teaching, in particular, Denis delivered general physics practicum as well as seminars on theoretical and quantum mechanics. His research activities were addressed mainly to optical and structural properties of semiconductor quantum dots and Si-based nanostructures. During his studies he was involved in a number of projects, funded by RFBR and the Ministry of Education and Science, both as a participant and a leader. Denis performed also the numerous research visits abroad, participating in EU projects and scientific exchange programmes funded by German Academic Exchange Service (DAAD), German-Russian Interdisciplinary Science Center (G-RISC) or Erasmus+. In 2015 he was promoted to senior research scientist position at MSU. His current scientific interests are focused on all-dielectric metamaterials and plasmonic nanostructures.
Abstract: The talk is devoted to a recently introduced femtosecond laser printing technique, which was further developed for the fabrication of crystalline single spherical nanoparticles from thin donor films. The developed approach is based on a laserinduced forward transfer process, which provides an opportunity for nanoparticle controlled positioning on different types of receiver substrates. The transfer of crystalline Ge and SiGe nanoparticles from an amorphous donor films has been demonstrated for the first time. The size of the generated nanoparticles was varied from about 100 to 300 nm depending on the laser pulse energy and wavelength. The crystallinity and composition of nanoparticles are both confirmed by the Raman spectroscopy measurements. The experimental visible scattering spectra of single nanoparticles are found to be well coincident with the theoretical simulations performed on the basis of Mie theory. The specific features of linear and nonlinear optical response of nanoparticles in the visible and near-infrared spectral ranges are discussed.