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Surface Phonons (surface + phonon)
Selected AbstractsSurface phonons in CdS1,xSex nanoparticles embedded in a dielectric mediumPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2009Yu. M. Azhniuk Abstract Raman scattering by surface phonons in CdS1,xSex nanocrystals grown in a borosilicate glass matrix, is studied. CdSe-like and CdS-like surface phonon frequencies are shown to increase with the relevant component content in the nanocrystal composition. No clear size dependence of the surface phonon frequencies has been observed. On the other hand, surface phonons in CdS1,xSex nanocrystals exhibit resonant dependence on the Raman excitation wavelength. It is emphasized that measurements of Raman scattering by surface phonons in CdS1,xSex nanocrystals give no reason to judge upon the nanocrystal shape. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Size-dependent Raman and infrared studies of PbSe nanoparticlesJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2008F. S. Manciu Abstract Micro-probe Raman and far-infrared absorption spectroscopies were used to prove the existence of optical phonon modes of PbSe nanoparticles prepared by colloidal chemistry and preliminarily characterized by transmission electron microscopy. To the best of our knowledge, this is the first time that evidence of the surface phonon (SP) mode by Raman spectroscopy has been experimentally observed. The wavenumber of the SP mode is consistent with its prediction by a dielectric continuum model. While for different PbSe nanoparticle sizes the observed SP mode does not show any obvious change in its position, there is a clear shift by approximately 4 cm,1 toward higher wavenumber in the appearance of the LO(,) in the Raman spectra from the 3 nm to the 7 nm PbSe nanoparticles. Far-infrared measurements demonstrate the presence of the transverse optical TO(,) and of the coupled phonon modes. Copyright © 2008 John Wiley & Sons, Ltd. [source] Surface phonons in CdS1,xSex nanoparticles embedded in a dielectric mediumPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2009Yu. M. Azhniuk Abstract Raman scattering by surface phonons in CdS1,xSex nanocrystals grown in a borosilicate glass matrix, is studied. CdSe-like and CdS-like surface phonon frequencies are shown to increase with the relevant component content in the nanocrystal composition. No clear size dependence of the surface phonon frequencies has been observed. On the other hand, surface phonons in CdS1,xSex nanocrystals exhibit resonant dependence on the Raman excitation wavelength. It is emphasized that measurements of Raman scattering by surface phonons in CdS1,xSex nanocrystals give no reason to judge upon the nanocrystal shape. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Imaging of surface phonons on a spherePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2004Hiroto Yamazaki Abstract Surface phonon wavepackets are generated on aluminium-coated transparent glass balls on irradiation with ultrashort light pulses. Delayed ultrashort probe light pulses are used to image the surface phonon propagation in real time by simply monitoring the modulation in the reflected probe beam intensity caused by the photoelastic effect. Imaging was achieved in the region of the phonon source and at the opposite pole of the sphere. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Thermal dynamics at surfacesANNALEN DER PHYSIK, Issue 10-11 2009H. Brune Abstract The present paper describes what happens at the surface of a crystal as its temperature steadily increases from zero Kelvin close to the bulk melting temperature. We treat thermal motion, such as the diffusion of individual adatoms establishing mass transport, the formation of adatom or vacancy gases coexisting with islands or steps of the condensed phase, surface phonons and the anharmonicity of the surface potential being markedly different from the one in bulk, as well as thermally induced reconstructions, surface roughening, and finally surface melting, which usually well precedes bulk melting. The paper intends to give an overview with references to the original and review literature. [source] Thermal dynamics at surfacesANNALEN DER PHYSIK, Issue 10-11 2009H. Brune Abstract The present paper describes what happens at the surface of a crystal as its temperature steadily increases from zero Kelvin close to the bulk melting temperature. We treat thermal motion, such as the diffusion of individual adatoms establishing mass transport, the formation of adatom or vacancy gases coexisting with islands or steps of the condensed phase, surface phonons and the anharmonicity of the surface potential being markedly different from the one in bulk, as well as thermally induced reconstructions, surface roughening, and finally surface melting, which usually well precedes bulk melting. The paper intends to give an overview with references to the original and review literature. [source] | ||||||||||