PHOTOINDUCED PHENOMENA IN Sr1-xCaxTiO3, 0 ≤ x ≤ 0.12

被引：21

作者：

Basun, S. A. ^{[1
]}

Bianchi, U. ^{[2
]}

Bursian, V. E. ^{[1
]}

Kaplyanskii, A. A. ^{[1
]}

Kleemann, W. ^{[2
]}

Markovin, P. A. ^{[1
]}

Sochava, L. S. ^{[1
]}

Vikhnin, V. S. ^{[1
]}

机构：

[1] AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia

[2] Gerhard Mercator Univ, D-47048 Duisburg, Germany

来源：

FERROELECTRICS | 1996年 / 183卷

关键词：

D O I：

10.1080/00150199608224112

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Photoinduced changes of the spectral, temperature and time dependences of the conductivity, the Cr(3+) R-luminescence, the electron paramagnetic resonance, the refractive index and of the spatial variation of the linear birefiingence are measured in nominally pure SrTiO(3) and ferroelectric Sr(1-x)Ca(x)TiO(3) (x=0.007 and 0.12). In both materials a large, long time persisting increase of the photoconductivity for light with energy less than 2.1 eV was found as a result of previous illumination with higher photon energies. This memory threshold coincides with the low energy edge of the strongest extrinsic band in the excitation spectra. Basic mechanisms of extrinsic photoelectronic processes in both materials are proposed. They involve a parallel action of (i) photoinduced charge transfer from the valence to the conduction band via deep energy levels within the gap, (i) recombination due to Cr(3+)-Cr(4+) centers, and (iii) trapping and light-induced emission processes via relatively shallow traps.

引用

页码：255 / 264

页数：10