摘要:

AbstractEmission and excitation spectra of BaS:Bi3+phosphors are measured at 300, 80, and 6 K. I n the excitation spectra the A and C excitation bands are observed. In the emission spectra only one band is observed which is assigned to the transition3A1u→1A1gon the basis of the measurement of the time‐resolved emission spectra and the decay constant of the phosphorescence. The diffused reflection spectra and the magnetic effect on the phonon structure of the emission band are also measured at 80 and 4.2 K, respectively. The former is compared with the excitation spectra. The reason why the emission band3T1u→1A1gcannot be observed at low temperatures is explained by the fact that the probability of the tunnel effect3T1u→3A1uis larger than that of the luminescent transition3T

ISSN:0370-1972    

DOI:10.1002/pssb.2221330139

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe optical properties of EuF3and GdF3are reinvestigated. Crystal field parameters derived from the data by using the D3h→ C2vdescending symmetry procedure for EuF3are (in cm−1):B 02= 465,B 22= 375,B 04= −232,B 24= −96,B 44= −114,B 06= −490,B 26= 83,B 46= −518,B 66= −162. The temperature dependent paramagnetic susceptibility of EuF3, is calculated by using the simulated wave functions. The calculated and experimental paramagnetic susceptibi

ISSN:0370-1972    

DOI:10.1002/pssb.2221330140

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractResults concerning the influence of hydrostatic pressure, uniaxial stress, and temperature on the spin‐Hamiltonian parameters of Cr3+in α‐LiIO3, single crystals are reported. Assuming that the local compressibility and thermal expansion of the nearest surroundings of the Cr3+ion is the same as of α‐LiIO3crystal lattice it is shown that the temperature and pressure variations on theD‐parameter are mainly due to thermal expansion and compressibility of the lattice, whereas the contribution from spin‐phonon interactions is several times smaller. The deformation of the oxygen octahedron close to the Cr3+ion is

ISSN:0370-1972    

DOI:10.1002/pssb.2221330141

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe shape of the Mössbauer relaxation pattern is derived for a Mössbauer ion performing an arbitrary diffusive motion; the formulae used in the literature follow as particular case

ISSN:0370-1972    

DOI:10.1002/pssb.2221330142

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe X‐ray absorption K‐edge spectrum of titanium in (Ti, Nb)O2, rutile or pseudo‐rutile solid solutions is recorded. The second derivative spectra are used to measure the energy shift of the transitions. A partial transfer of Nb 4d electron onto Ti 3d orbitals is found implying a similar energy of these orbitals. On the other hand a decrease of the crystal field is observed when Nb content increases. This may arise from the increase of the mean number of conduction electrons or the increase of the mean size of the metallic octahedron. Lastly, because the electronic structure of the titanium evolves continuously with the niobium content, niobium is certainly randomly distributed around the tit

ISSN:0370-1972    

DOI:10.1002/pssb.2221330143

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA detailed study of the time‐resolved luminescence of CdGaInS4, after pulsed laser excitation atT= 30 K is presented. Results are given on the time‐resolved spectra in the range 50 ns to 10 ms of delay time with respect to excitation, on the time decay of the luminescence intensity at 610 nm, and on the time evolution of the integrated luminescence intensity for different emission wavelengths. Finally a simple model is presented for the recombination processes at low temperatures yielding good agreement with the experimental d

ISSN:0370-1972    

DOI:10.1002/pssb.2221330144

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractAn energy‐loss‐method formalism applicable to a thin quantized film is developed. Within the frame of a self‐consistent field and taking into account the “imaginary” charges in the film surrounding regions the expression for a film dielectric function is derived and, in the long‐wavelength limit the analytical form of its imaginary part is found for a simple model of a size quantized film. Under the condition that the electron gas is nondegenerate and only the first subband is filled, the mobility is calculated, when an electron‐ionized impurity scattering is taken into account, and compared with the relevant Boltzma

ISSN:0370-1972    

DOI:10.1002/pssb.2221330145

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractExcess hole and excess electron mobilities are studied in 2–2′ bipyridine and pyridazino [4,5‐d] pridazine using tight binding approximation. With suitable molecular orbitals for band structure and using a potential given by Silbey et al. the energy bands are calculated. The applicability of band model and the suitability of these materials for organic photovoltaic devices are discussed in the light of existing the

ISSN:0370-1972    

DOI:10.1002/pssb.2221330146

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe properties of a two‐dimensional electronic system in n‐inversion layers in grain boundaries of p‐InSb bicrystals are investigated under high hydrostatic pressure (up to 103MPa) in high magnetic fields (up to 14 T). A rapid decrease of the carrier concentration in the inversion layer is observed when hydrostatic pressure is applied. At high pressures and high magnetic fields it is experimentally verified that the Hall resistivity ϱxyis quantized into integer multiplies

ISSN:0370-1972    

DOI:10.1002/pssb.2221330147

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe Boltzmann equation is investigated in the presence of strong and time‐dependent electromagnetic fields taking into account the intra‐collisional field effect. The expression obtained for the field‐induced tail of the electron‐phonon scattering rate leads to the known results for static fields at low frequencies and includes at higher frequencies multiphoton pr

ISSN:0370-1972    

DOI:10.1002/pssb.2221330148

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY