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101.
T. Geppert S.L. Schweizer U. Gösele R.B. Wehrspohn 《Applied Physics A: Materials Science & Processing》2006,84(3):237-242
We present a method to create at the same time trenches and ordered macropore arrays during photo-electrochemical etching of n-type silicon. This novel method allows in situ separation of single devices with a submicrometer precision. It also enables new device structures in macroporous silicon in the areas of photonics, sensing and electronics. The limits of this new process are simulated using electrostatic models and are verified experimentally. PACS 82.45.Yz; 81.16.-c 相似文献
102.
Z. U. Dzhabua T. O. Dadiani A. V. Gigineishvili M. Yu. Stamateli K. D. Davitadze G. N. Iluridze 《Physics of the Solid State》2006,48(8):1481-1485
A technique for preparing γ-Nd2S3 crystalline thin films through discrete vacuum thermal evaporation of a presynthesized bulk material is developed. The films deposited are doped with cadmium and lead. The reflectance and transmittance spectra of the films are measured in the photon energy range 0.2–3.0 eV at a temperature of 300 K. The frequency analysis of the absorption coefficient demonstrates that the γ-Nd2S3 films are characterized by an exponential absorption edge. The photoconductivity spectra and temperature dependences of the photoconductivity for the γ-Nd2S3 films doped with cadmium and lead are measured in the photon energy range 0.2–3.3 eV at temperatures varying from 115 to 380 K. The experimental data obtained are interpreted under the assumption that the acceptor levels formed by vacancies in the cation sublattice and compensated for by cadmium and lead donor dopants play a crucial role in the photoconduction. The ionization energy at the lead donor level is determined. 相似文献
103.
104.
Suppose that K
d is compact and that we are given a function fC(K) together with distinct points xiK, 1in. Radial basis interpolation consists of choosing a fixed (basis) function g :
+→
and looking for a linear combination of the translates g(|x−xj|) which interpolates f at the given points. Specifically, we look for coefficients cj
such that
has the property that F(xi)=f(xi), 1in. The Fekete-type points of this process are those for which the associated interpolation matrix [g(|xi−xj|)]1i,jn has determinant as large as possible (in absolute value). In this work, we show that, in the univariate case, for a broad class of functions g, among all point sequences which are (strongly) asymptotically distributed according to a weight function, the equally spaced points give the asymptotically largest determinant. This gives strong evidence that the Fekete points themselves are indeed asymptotically equally spaced. 相似文献
105.
I. N. Koprinarov U. Müller-Jahreis P. Thiele 《Applied Physics A: Materials Science & Processing》1996,62(6):565-570
The crystalline-amorphous transition in GaAs induced by Ar ions (energy 1–3 keV) has been investigated using single-wavelength ellipsometry. The experiments have been performed in-situ at room temperature. Ion damage straggling, amorphization threshold and critical energy density have been derived by means of a simple analytical model for the growth of the amorphous layer. This model is discussed and the corresponding calculations are found to be in satisfactory agreement with experimental data. 相似文献
106.
Walter Feit 《Israel Journal of Mathematics》1993,82(1-3):141-156
LetK be a field and letG be a finite group.G isK-admissible if there exists a Galois extensionL ofK withG=Gal(L/K) such thatL is a maximal subfield of a centralK-division algebra. This paper contains a characterization of those number fields which areQ
16-admissible. This is the same class of number fields which are 2A
6=SL(2, 9) and 2A
7 admissible.
Dedicated to John Thompson to celebrate his Wolf Prize in Mathematics 1992 相似文献
107.
The aim of this contribution is to study lanthanum containing fullerenes produced and treated under different conditions. The work was done using solid soot extract giving poorly resolved ESR spectra or separated lanthanofullerenes in solution showing well resolved ESR spectra. ESR experiments in connection with the mass spectrometry give information on the electronic states due to the electron transfer from the endohedral metal to the fullerene cage and the influence of oxygen on endohedral lanthanofullerene. The analysis of ESR spectra indicates the presence of up to nine octets of lanthanum containing fullerenes. These species have different stabilities. Furthermore, a very narrow single ESR line in the lanthanofullerene spectrum was detected having a linewidth ΔB=0.008 mT and ag-factor 2.0025. The electron transfer to the endohedral La@C82 molecule studied by voltammetry and electrochemicalin situ ESR experiments is described. The interaction of the lanthanofullerene with oxygen in solution is also studied. In different solvents the influence of oxygen on line broadening in the ESR spectra of La@C82 was observed. 相似文献
108.
H. Günther M. Foerste M. Kunze G. zu Putlitz U. von Stein 《Zeitschrift für Physik B Condensed Matter》1996,100(4):613-617
We review the previous conclusion [J.Y. Ryu, Y.C. Chung and S.D. Choi, Phys. Rev. B 32, 7769 (1984)] that the trace property Tr(ABC) = Tr(CAB) leads to two different cyclotron transition absorption formulae in the electron-phonon systems in the lowest order approximation. The pictorial expression and the calculated linewidths in Ge and Si show that the socalled EWC scheme is more seeming than the socalled MWC scheme. The difference is expected to disappear if we take into account all the higher order perturbation terms or start with the many body formalism in the complete scheme. 相似文献
109.
The sensitivity of neutron-proton scattering observables to the recently reported charge-independence breaking of the isospinT=13
P nucleon-nucleon interaction has been calculated. It is shown that only the analyzing powerA
y
() at extreme forward angles and at =90° c.m. and the spin-correlation coefficientA
zx
() at 90° c.m. exhibit a measurable sensitivity. It is concluded that the determination ofA
y
at 90° c.m. is currently the most accurate approach to verify independently charge-independence breaking in the3
P nucleon-nucleon phase shifts, considering the status of present experimental techniques. 相似文献
110.
H. Fawcett S. Barlag H. Becker E. Belau T. Böhringer M. Bosman V. Castillo V. Chabaud D. Bucholz C. Damerell C. Daum G. De Rijk H. Dietl S. Gill A. Gillman R. Gilmore T. Gooch P. Gras Z. Hajduk E. Higon B. Hyams D. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé G. Polok J. Richardson M. Rozanska K. Rybicki H. Seebrunner U. Stierlin R. Tapper H. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):513-519
The production of the neutralK ? (892) resonances by 200 GeVK ? andπ ? has been studied over the kinematic range 0.0<x f<1.0 andp t 2 <5.0 GeV2. Longitudinal and transverse momentum distributions are presented. In addition the decay angular distributions inK ? fragmentation to \(\bar K^{0*} \) have been investigated. 相似文献