Nanotechnology and Photovoltaic Devices

Jan Valenta is professor of quantum optics and optoelectronics at the Department of Chemical Physics and Optics, Charles University, Prague. His research is oriented toward optical properties of semiconductor nanostructures, especially silicon. He is developing special spectroscopy set-ups and methods to measure photo- and electroluminescence spectra (down to single nano-objects), optical gain, and absolute quantum yields. His other interests include the history of science, scientific photography, and science-for-art applications. He is co-author (with I. Pelant) of the textbook Luminescence Spectroscopy of Semiconductors (Oxford, 2012). Salvo Mirabella received his laurea (1999) and PhD (2003) in physics from the University of Catania, Italy, and is now researcher at the Institute for Microelectronics and Microsystems, National Council of Research (CNR IMM), Italy. His research activity is mainly experimental, focusing on group IV advanced materials for applications in photovoltaics (light absorption mechanisms in Si- or Ge-based nanostructures, sunlight-energy conversion, and transparent conductive electrodes) and microelectronics (point-defect engineering and dopant diffusion in crystalline or amorphous semiconductors and ion beam modification of materials).

Introduction to photovoltaics and potential applications of group IV nanostructures. Dielectric function and spectrophotometry: from bulk to nanostructures. Ab initio calculations of the electronic and optical properties of group IV semiconductor nanostructures embedded in different matrices. Silicon nanoclusters embedded in dielectric matrices: nucleation, growth, crystallization, defects. Excited-state relaxation in group IV nanocrystals investigated using optical methods. Carrier multiplication in isolated and interacting silicon nanocrystals. The introduction of majority carriers into group IV nanocrystals. Electrical transport in Si-based nanostructured superlattices. Ge nanostructures for harvesting and detection of light. Application of surface-engineered silicon nanocrystals with quantum confinement and carbon nanomaterials in solar cells. Prototype PV cells with Si nanoclusters.