Absorption, photoluminescence, and Raman scattering studies of CdSxSe1-x nanocrystals, as a function of the crystallite mean radius, are reported. By properly considering the competing effects of spatial localization and strain, the chemical composition and the lattice contraction are assessed. Two different techniques have been used to analyze the electron-phonon coupling. Photoluminescence and absorption studies allow us to measure the Huang-Rhys parameter. The size dependence of the Frohlich electron-LO phonon interaction has been extracted, for the first time, from the polarization analysis of the Raman scattering. Our results unambiguously show that, in the investigated nanocrystal size range, the electron-phonon coupling monotonically increases at decreasing the nanocrystal radius. The observed behavior is in agreement with the latest calculations
Optical phonons and electron-phonon coupling in CdSxSe1-x quantum dots / Spagnolo, Vincenzo Luigi; Scamarcio, Gaetano; Ventruti, G.; Lugara, M.; Ferrara, Michele; Marie Catalano, Ida; Righini, Giancarlo C.. - STAMPA. - 2648:(1995), pp. 460-469. (Intervento presentato al convegno International Conference on Optical Diagnostics of Materials and Devices for Optoelectronics, Microelectronics and Quantum Electronics tenutosi a Kiev, Ukraine nel May 11-13, 1995) [10.1117/12.226211].
Optical phonons and electron-phonon coupling in CdSxSe1-x quantum dots
Vincenzo Spagnolo;
1995-01-01
Abstract
Absorption, photoluminescence, and Raman scattering studies of CdSxSe1-x nanocrystals, as a function of the crystallite mean radius, are reported. By properly considering the competing effects of spatial localization and strain, the chemical composition and the lattice contraction are assessed. Two different techniques have been used to analyze the electron-phonon coupling. Photoluminescence and absorption studies allow us to measure the Huang-Rhys parameter. The size dependence of the Frohlich electron-LO phonon interaction has been extracted, for the first time, from the polarization analysis of the Raman scattering. Our results unambiguously show that, in the investigated nanocrystal size range, the electron-phonon coupling monotonically increases at decreasing the nanocrystal radius. The observed behavior is in agreement with the latest calculationsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
