Zobrazeno 1 - 10
of 25
pro vyhledávání: '"R. Scharfschwerdt"'
Publikováno v:
Solid State Communications. 116:133-136
In BaTiO3 a paramagnetic defect is identified by EPR which is attributed to a paramagnetic S=1/2 ion off-center near a Ba site. Twelve magnetically distinguishable sites contribute to the angular dependence pattern of the spectra, each of the sites b
Publikováno v:
Applied Physics B: Lasers and Optics. 67:79-86
crystals are given. The extension of this type of spectroscopy to other fields, where correlation between EPR and optical phenomena is essential, is discussed.
Publikováno v:
Physical Review B. 54:15284-15290
Using electron paramagnetic resonance two types of ${\mathrm{Ti}}^{3+}$-related centers are identified in BaTi${\mathrm{O}}_{3}$, which are attributed to ${\mathrm{Ti}}^{3+}$-${V}_{\mathrm{O}}$ and to ${\mathrm{Ti}}^{3+}$-${V}_{\mathrm{O}}$ associate
Publikováno v:
Ferroelectrics. 185:9-12
Depending on the acceptor content of BaTiO3 crystals, two types of Ti3+ ESR signals are observed. Acceptor-poor samples, which thus also have low concentrations of compensating oxygen vacancies, Vo, contain isolated Ti3+ free small polarons. Acceptor
Publikováno v:
Physical Review B. 53:116-125
In ${\mathrm{BaTiO}}_{3}$ the alkali ions Na and K, replacing Ba, lead to acceptor levels about 50 meV above the valence band edge. The structure of these defects can be studied by electron spin resonance, after light induced valence-band holes have
Publikováno v:
Applied Physics B Laser and Optics. 61:1-7
By combined studies of electron spin resonance and optical absorption at low temperatures, the charge-transfer bands of Rh5+ and Rh4+ are identified to be peaked near 1.6 and 1.9 eV, respectively. On this basis, the light-induced charge-transfer proc
Autor:
H. Hesse, T. Varnhorst, O. F. Schirmer, R. Scharfschwerdt, C. Kuper, E. Possenriede, H. Kröse
Publikováno v:
Optical Materials. 4:153-157
An optical method is presented which allows to identify at room temperature the photoinduced charge transfers between different defects in photorefractive crystals. The analysis is based on the labelling of the opticfal spectra with the corresponding
Publikováno v:
Ferroelectrics. 151:199-204
Two shallow O- trapped hole centers in BaTiO3 are identified to arise from association with Na+ and Ptx+. In material with decreased acceptor concentration, ESR of Ti3+ small polarons and Ti3+-Nb5+ pairs is found. The role of such centers in light in
Autor:
Georg F. Hoffmann, S. R. Scharfschwerdt, Yoon S. Shin, K. M. Gibson, S. U. Brendel, I. M. Speidel
Publikováno v:
Journal of Inherited Metabolic Disease. 15:738-746
Mevalonic aciduria due to mevalonate kinase deficiency, an inherited defect of cholesterol biosynthesis, has presented with clinical variability in 10 patients from 7 families. We sought to define a genetic basis for this heterogeneity by determining
Autor:
G. Pauliat, G. Roosen, Daniel Rytz, R. Scharfschwerdt, J.M.C. Jonathan, Nicolas Huot, O.F. Schirmer
Publikováno v:
CLEO/Europe Conference on Lasers and Electro-Optics.