Phonon structure of amorphous germanium by inelastic electron tunnelling spectroscopy
نویسندگان
چکیده
Measurements of inelastic electron tunnelling through barriers of amorphous germanium are reported. The data are analysed using a theory of the electron-phonon interaction which includes phonon correlations. The vibrational density of states obtained from the experimental data is in agreement with that expected for amorphous germanium containing a broad distribution of bond angle variations.
منابع مشابه
PHONON STRUCTURE OF AMORPHOUS SiO x BY INELASTIC TUNNELLING SPECTROSCOPY
We present phonon spectra of very thin evaporated amorphous films of SiOx, obtained by inelastic electron tunnelling spectroscopy. The broad features of the results are similar to those found in neutron-scattering, Raman and infra-red measurements on bulk vitreous SiO2 but there are differences of detail. The results show inelastic tunnelling spectroscopy to be a powerful technique for the stud...
متن کاملPhonon and plasmon excitation in inelastic electron tunneling spectroscopy of graphite
The inelastic electron tunneling spectrum ~IETS! of highly oriented pyrolitic graphite has been measured with scanning tunneling spectroscopy ~STS! at 6 K. The observed spectral features are in very good agreement with the vibrational density of states of graphite calculated from first principles. We discuss the enhancement of certain phonon modes by phonon-assisted tunneling in STS based on th...
متن کاملElastic and inelastic scattering in electron momentum spectroscopy of amorphous Ge films
Electron momentum spectroscopy (an (e, 2e) experiment in the high-energy and large momentum transfer limit) is a scattering approach to the study of the electronic structure. The intensity observed in these experiment is, for an infinitely thin film, simply proportional to the spectral momentum density. For experiments using free-standing films of a more realistic thickness (100 Å or so), elast...
متن کاملELECTRON TUNNELLING IN HIGH-Tc”Nb3Ge” FILMS
Energy gap structure associated with superconducting Nb,Ge has been observed on the normal side of Al-Nb3Ge proximity sandwiches. The possible use of tunnelling junctions of this type to study the electron-phonon spectra of Ift̂ Ge is pointed out. Single particle tunnelling measurements are in principle a powerful technique for obtaining the electron-phonon spectral function aF(w). While procedu...
متن کاملSpatially resolved Raman spectroscopy on indium-catalyzed core-shell germanium nanowires: size effects.
The structure of indium-catalyzed germanium nanowires is investigated by atomic force microscopy, scanning confocal Raman spectroscopy and transmission electron microscopy. The nanowires are formed by a crystalline core and an amorphous shell. We find that the diameter of the crystalline core varies along the nanowire, down to few nanometers. Phonon confinement effects are observed in the regio...
متن کامل