Accueil >
Production scientifique
(321) Production(s) de GIL B.
|
|
k.P energy band structure of ZnO/Zn1-xMgxO quantum well heterostructures
Auteur(s): Zitouni K., Kadri A., Lefebvre P., Gil B.
Conference: E-MRS Spring Meeting (Strasbourg, FR, 2005-05-31)
Actes de conférence: Superlattices and Microstructures, vol. 39 p.91 (2006)
Texte intégral en Openaccess :
Ref HAL: hal-00389991_v1
DOI: 10.1016/j.spmi.2005.08.033
WoS: 000235433200012
Exporter : BibTex | endNote
24 Citations
Résumé: We present a k.P theoretical study of the energy band properties of würtzite ZnO/Zn1−xMgxO Quantum Well Heterostructures (QWH) as a function of the alloy composition x in the range x<0.4, and for various well widths. For this purpose, we use a Luttinger-type effective mass model, the 6×6 Rashba–Sheka–Pikus model, to describe the valence bands of these QWH. By using the k.P parameters available in the literature, we have first computed the energy band-structure dispersion of bulk ZnO and we have found good agreement with previous k.P, as well as, ASA-LMPTO results. Then we have computed the valence band dispersion and confinement energies in the range of interest x<0.40 and for various well widths LZ. Good agreement is found with the available pump–probe PL results, for the peak energies of linear absorption for various QWH are closely fitted.
Commentaires: poster
|
|
|
Study of Sharp Photoluminescence Spectra of Individual GaN/AlN Quantum Dots. Spectral Diffusion Effects.
Auteur(s): Bardoux Richard, Guillet T., Lefebvre P., Taliercio T., Bretagnon T., Gil B., Semond F.
Conference: International Workshop on Nitrides Semiconductors (IWN) (Kyoto, JP, 2006-10-22)
|
|
|
Raman scattering by the longitudinal optical phonon in InN: Wave-vector nonconserving mechanisms
Auteur(s): Demangeot F., Pinquier C., Frandon J., Gaio M., Briot O., Maleyre Benedicte, Ruffenach S., Gil B.
(Article) Publié:
Physical Review B, vol. 71 p.104305 (2005)
Ref HAL: hal-00540408_v1
DOI: 10.1103/PhysRevB.71.104305
WoS: 000228065400035
Exporter : BibTex | endNote
49 Citations
Résumé: We have studied plasmon-longitudinal optical (LO) phonon coupled modes by means of Raman scattering in n-type InN layers grown by metalorganic vapor phase epitaxy, for carrier densities in the range of 10(19) cm(-3). A strong mode is observed near the frequency of the A(1)(LO) phonon, despite the high conductivity of the films. It is suggested that the main origin which can be invoked for an effective decoupling of the LO phonon from the plasmon is the participation to the scattering of phonons with wave vectors larger than the Thomas-Fermi wave vector. The line shape of the LO mode is calculated using the Lindhard-Mermin dielectric function taking into account finite wave-vectors, for various light scattering processes. We find that the charge density fluctuations mechanism is involved as the main scattering mechanism in n-type InN, at least for the investigated excitation energies in the 2.54-1.89 eV range. The breakdown of the wave-vector conservation is assigned to electron elastic scattering by impurities.
|
|
|
Radiative and nonradiative recombination processes in InN films grown by metal organic chemical vapor deposition
Auteur(s): Intartaglia R., Maleyre Benedicte, Ruffenach S., Briot O., Taliercio T., Gil B.
(Article) Publié:
Applied Physics Letters, vol. 86 p.142104 (2005)
Ref HAL: hal-00540409_v1
DOI: 10.1063/1.1897428
WoS: 000228242700030
Exporter : BibTex | endNote
34 Citations
Résumé: The 800 meV photoluminescence band in indium nitride is excited under pulsed excitation conditions and is investigated as a function of temperature and time. Our results are consistent with a composite photoluminescence feature composed of two overlapping bands separated by an similar to 10 meV splitting, with populations described by a thermal equilibrium model. Efficient nonradiative recombination channels rule both the temperature dependence of the time-integrated photoluminescence spectra and the recombination dynamics. At 10 K, the radiative recombination time is of the order of 300 ns, while the nonradiative recombination time, which is ruled by activation energy of 8 meV, is about 100 ps. (C) 2005 American Institute of Physics.
|