Showing
10, 25, 50, 100, 500, 1000, all papers per page.
Sort by:
last publication date,
older publication date,
last update date.
- 201. Phys. Rev. B 75, 045429 (2007) , “Electron spin relaxation in semiconducting carbon nanotubes: The role of hyperfine interaction”, Y. G. Semenov, K. W. Kim, and G. J. IafrateA theory of electron spin relaxation in semiconducting carbon nanotubes is developed based on the hyperfine interaction with disordered nuclei spins I=1/2 of 13C isotopes. It is shown that strong radial confinement of electrons enhances the electron-nuclear overlap and subsequently... (Read more)
- 202. Phys. Rev. B 75, 045301 (2007) , “Ionization energy of donor and acceptor impurities in semiconductor nanowires: Importance of dielectric confinement”, Mamadou Diarra, Yann-Michel Niquet, Christophe Delerue, and Guy AllanCalculations of the electronic states of donor and acceptor impurities in nanowires show that the ionization energy of the impurities is strongly enhanced with respect to the bulk, above all when the wires are embedded in a material with a low dielectric constant. In free-standing nanowires with... (Read more)
- 203. Phys. Rev. B 75, 045211 (2007) , “Ab initio supercell calculations on aluminum-related defects in SiC”, A. Gali, T. Hornos, N. T. Son, E. Janzén, and W. J. ChoykeAb initio supercell calculations of the binding energies predict complex formation between aluminum and carbon interstitials in SiC. In high-energy implanted SiC aluminum acceptor can form very stable complexes with two carbon interstitials. We also show that carbon vacancy can be attached to... (Read more)
- 204. Phys. Rev. B 75, 045210 (2007) , “Positron trapping kinetics in thermally generated vacancy donor complexes in highly As-doped silicon”, K. Kuitunen, K. Saarinen, and F. TuomistoWe have measured positron lifetime and Doppler broadening in highly As-doped silicon containing thermally generated V-As3 defect complexes (vacancy is surrounded by three arsenic atoms). We observe positron detrapping from the V-As3 defect complex and determine... (Read more)
- 205. Phys. Rev. B 75, 045201 (2007) , “Ab initio models of amorphous Si1−xGex:H”, T. A. Abtew and D. A. DraboldWe study the structural, dynamical, and electronic properties of amorphous Si1−xGex:H alloys using first-principles local basis molecular dynamics techniques. The network topology and defects in the amorphous network have been analyzed. Structural changes,... (Read more)
- 206. Phys. Rev. B 75, 045107 (2007) , “Multiband effects in the electron spin resonance of Gd3+ in the intermediate-valence compound YbAl3 and its reference compound LuAl3”, R. R. Urbano, E. M. Bittar, M. A. Pires, L. Mendonça Ferreira, L. Bufaiçal, C. Rettori, P. G. Pagliuso, B. Magill, S. B. Oseroff, J. D. Thompson, and J. L. SarraoElectron spin resonance (ESR) results of Gd3+ in YbAl3 and LuAl3 are analyzed using a multiband (f-, d-, and p-type) model of correlated conduction electrons. The need for a multiband analysis of our results is based on the following... (Read more)
- 207. Phys. Rev. B 75, 035322 (2007) , “Ab initio study of electronic and magnetic properties of the C-codoped Ga1−xMnxN (100) surface”, Q. Wang, Q. Sun, and P. JenaFirst principles calculations based on gradient corrected density functional theory have been carried out to study the magnetic coupling between Mn atoms in pure and carbon doped Ga1−xMnxN thin films. We show that the ground state of Mn-doped GaN (100) thin... (Read more)
- 208. Phys. Rev. B 75, 035309 (2007) , “Role of hydrogen in hydrogen-induced layer exfoliation of germanium”, J. M. Zahler, A. Fontcuberta i Morral, M. J. Griggs, Harry A. Atwater, and Y. J. ChabalThe role of hydrogen in the exfoliation of Ge is studied using cross-sectional transmission electron microscopy, atomic force microscopy, and multiple-internal transmission mode Fourier-transform infrared absorption spectroscopy and compared with the mechanism in silicon. A qualitative model for the... (Read more)
- 209. Phys. Rev. B 75, 035211 (2007) , “Self- and foreign-atom diffusion in semiconductor isotope heterostructures. II. Experimental results for silicon”, H. Bracht, H. H. Silvestri, I. D. Sharp, and E. E. HallerWe report the diffusion of boron, arsenic, and phosphorus in silicon isotope multilayer structures at temperatures between 850 °C and 1100 °C. The diffusion of all dopants and self-atoms at a given temperature is modeled with the same setting of all native-point-defect-related parameters.... (Read more)
- 210. Phys. Rev. B 75, 035210 (2007) , “Self- and foreign-atom diffusion in semiconductor isotope heterostructures. I. Continuum theoretical calculations”, H. BrachtDopant diffusion experiments in semiconductors yield the mobility of the element of interest and information about the possible mechanisms of atomic diffusion. In many cases the diffusion is described on the basis of Fick's law of diffusion, but this treatment is often too simple. In this paper,... (Read more)
- 211. Phys. Rev. B 75, 033303 (2007) , “Excitons in silicon nanocrystallites: The nature of luminescence”, Eleonora Luppi, Federico Iori, Rita Magri, Olivia Pulci, Stefano Ossicini, Elena Degoli, and Valerio OlevanoThe absorption and emission spectra of silicon nanocrystals up to 1 nm diameter have been calculated within a first-principles framework. Our calculations include geometry optimization and the many-body effects induced by the creation of an electron-hole pair. Starting from hydrogenated silicon... (Read more)
- 212. Phys. Rev. B 75, 033301 (2007) , “Microscopic evidence for evolution of superconductivity by effective carrier doping in boron-doped diamond: 11B-NMR study”, H. Mukuda, T. Tsuchida, A. Harada, Y. Kitaoka, T. Takenouchi, Y. Takano, M. Nagao, I. Sakaguchi, T. Oguchi, and H. KawaradaWe have investigated the superconductivity discovered in boron-doped diamonds by means of 11B-NMR on heteroepitaxially grown (111) and (100) films. 11B-NMR spectra for all of the films are identified to arise from the substitutional B(1) site as single occupation and lower... (Read more)
- 213. Phys. Rev. B 75, 024205 (2007) , “Mechanical strength and coordination defects in compressed silica glass: Molecular dynamics simulations”, Yunfeng Liang, Caetano R. Miranda, and Sandro ScandoloContrary to ordinary solids, which are normally known to harden by compression, the compressibility of SiO2 (silica) glass has a maximum at about 2–4 GPa and its mechanical strength shows a minimum around 10 GPa. At this pressure, the compression of silica glass undergoes a change... (Read more)
- 214. Phys. Rev. B 75, 024109 (2007) , “Optical and EPR properties of point defects at a crystalline silica surface: Ab initio embedded-cluster calculations”, L. Giordano, P. V. Sushko, G. Pacchioni, and A. L. ShlugerWe have studied the structure and spectroscopic properties of the paramagnetic nonbridging oxygen hole center and of the Egamma[prime]" align="middle"> center at the hydroxylated silica surfaces using density functional theory and an embedded-cluster model. To investigate the... (Read more)
- 215. Phys. Rev. B 75, 014111 (2007) , “Effects of vacancies on the properties of disordered ferroelectrics: A first-principles study”, L. Bellaiche, Jorge Íñiguez, Eric Cockayne, and B. P. BurtonA first-principles-based model is developed to investigate the influence of lead vacancies on the properties of the disordered Pb(Sc1/2Nb1/2)O3 (PSN) ferroelectric. Lead vacancies generate large, inhomogeneous, electric fields that reduce barriers between energy... (Read more)
- 216. Phys. Rev. B 75, 014102 (2007) , “First-principles study of vacancy formation in hydroxyapatite”, Katsuyuki Matsunaga and Akihide KuwabaraFirst-principles plane-wave calculations were performed for hydroxyapatite (HAp) in order to investigate the electronic structure and vacancy formation mechanisms. The HAp unit cell contains PO4 tetrahedra and OH groups formed by covalent P-O and H-O bonds. Ca ions play a role for... (Read more)
- 217. Phys. Rev. Lett. 99, 175502 (2007) , “Self-Interstitial in Germanium”, A. Carvalho, R. Jones, C. Janke, J. P. Goss, P. R. Briddon, J. Coutinho, and S. ÖbergLow-temperature radiation damage in n- and p-type Ge is strikingly different, reflecting the charge-dependent properties of vacancies and self-interstitials. We find, using density functional theory, that in Ge the interstitial is bistable, preferring a split configuration when neutral... (Read more)
- 218. Phys. Rev. Lett. 99, 136801 (2007) , “Electron Trapping at Point Defects on Hydroxylated Silica Surfaces”, Livia Giordano, Peter V. Sushko, Gianfranco Pacchioni, and Alexander L. ShlugerThe origin of electron trapping and negative charging of hydroxylated silica surfaces is predicted based on accurate quantum-mechanical calculations. The calculated electron affinities of the two dominant neutral paramagnetic defects, the nonbridging oxygen center, Si-O•, and the... (Read more)
- 219. Phys. Rev. Lett. 99, 085502 (2007) , “Nature of Native Defects in ZnO”, F. A. Selim, M. H. Weber, D. Solodovnikov, and K. G. LynnThis study revealed the nature of native defects and their roles in ZnO through positron annihilation and optical transmission measurements. It showed oxygen vacancies are the origin for the shift in the optical absorption band that causes the red or orange coloration. It also revealed experimental... (Read more)
- 220. Phys. Rev. Lett. 98, 265502 (2007) , “Monovacancy and Interstitial Migration in Ion-Implanted Silicon”, P. G. Coleman and C. P. BurrowsThe migration of monovacancies (V0) and self-interstitials (I) has been observed in ion-implanted low-doped float-zone silicon by variable-energy positron annihilation spectroscopy. V0 and I were created by the in situ implantation of ~20 keV... (Read more)
- 221. Phys. Rev. Lett. 98, 252501 (2007) , “Radioactive Decay Speedup at T=5 K: Electron-Capture Decay Rate of 7Be Encapsulated in C60”, T. Ohtsuki, K. Ohno, T. Morisato, T. Mitsugashira, K. Hirose, H. Yuki, and J. KasagiThe electron-capture (EC) decay rate of 7Be in C60 at the temperature of liquid helium (T=5 K) was measured and compared with the rate in Be metal at T=293 K. We found that the half-life of 7Be in endohedral C60... (Read more)
- 222. Phys. Rev. Lett. 98, 227401 (2007) , “Formation of Hydrogen Impurity States in Silicon and Insulators at Low Implantation Energies”, T. Prokscha, E. Morenzoni, D. G. Eshchenko, N. Garifianov, H. Glückler, R. Khasanov, H. Luetkens, and A. SuterThe formation of hydrogenlike muonium (Mu) has been studied as a function of implantation energy in intrinsic Si, thin films of condensed van der Waals gases (N2, Ne, Ar, Xe), fused and crystalline quartz, and sapphire. By varying the initial energy of positive muons... (Read more)
- 223. Phys. Rev. Lett. 98, 220501 (2007) , “Efficient Dynamic Nuclear Polarization at High Magnetic Fields”, Gavin W. Morley, Johan van Tol, Arzhang Ardavan, Kyriakos Porfyrakis, Jinying Zhang, and G. Andrew D. BriggsBy applying a new technique for dynamic nuclear polarization involving simultaneous excitation of electronic and nuclear transitions, we have enhanced the nuclear polarization of the nitrogen nuclei in 15N@C60 by a factor of 103 at a fixed temperature of 3 K and a... (Read more)
- 224. Phys. Rev. Lett. 98, 216803 (2007) , “High Mobility in LaAlO3/SrTiO3 Heterostructures: Origin, Dimensionality, and Perspectives”, G. Herranz, M. Basletić, M. Bibes, C. Carrétéro, E. Tafra, E. Jacquet, K. Bouzehouane, C. Deranlot, A. Hamzić, J.-M. Broto, A. Barthélémy, and A. FertWe have investigated the dimensionality and origin of the magnetotransport properties of LaAlO3 films epitaxially grown on TiO2-terminated SrTiO3(001) substrates. High-mobility conduction is observed at low deposition oxygen pressures... (Read more)
- 225. Phys. Rev. Lett. 98, 216601 (2007) , “Room Temperature Electrical Detection of Spin Coherence in C60”, W. Harneit, C. Boehme, S. Schaefer, K. Huebener, K. Fostiropoulos, and K. LipsAn experimental demonstration of electrical detection of coherent spin motion of weakly coupled, localized electron spins in thin fullerene C60 films at room temperature is presented. Pulsed electrically detected magnetic resonance experiments on vertical photocurrents through... (Read more)
Showing
10, 25, 50, 100, 500, 1000, all papers per page.
Sort by:
last publication date,
older publication date,
last update date.
All papers (3399)
Updated at 2010-07-20 16:50:39
Updated at 2010-07-20 16:50:39
(view as: tree
,
cloud
)
1329 | untagged |
Materials
(111 tags)
Others(101 tags)
Technique
(46 tags)
Details
(591 tags)
Bond(35 tags)
Defect(interstitial)(18 tags)
Defect(vacancy)(15 tags)
Defect-type(19 tags)
Element(65 tags)
Energy(8 tags)
Isotope(56 tags)
Label(303 tags)
Sample(17 tags)
Spin(8 tags)
Symmetry(15 tags)