Arizmendi, L. and Heras, C. De las and Jaque, F. and Suchocki, A. and Kobyakov, S. and Han, T. P. J. (2007) Photoconductivity in LiNbO3 crystals codoped with MgO and Cr2O3. Applied Physics B: Lasers and Optics, 87 (1). pp. 123-127. ISSN 0946-2171Full text not available in this repository. (Request a copy from the Strathclyde author)
The photoconductivity of LiNbO3 crystals codoped with Cr2O3 and different concentrations of MgO from 0 up to 6 mol % is reported. The spectral excitation of photocurrent presents an intense band corresponding to the Cr3+ induced blue absorption edge, but illuminating at the (4)A(2) -> T-4(1) ionic transition band a weak photocurrent is also excited. The photoconductivity is interpreted in terms of Cr3+ ionization and the formation of Nb-Nb(4+) small polarons as charge carriers. Photoconductivity below about 140 K is suppressed. The analysis of the photocurrent temperature dependence results in a 0.14 +/- 0.02 eV binding energy of the polaron at low temperature. Photoconductivity induced by excitation in the intraionic Cr3+ can be explained by a tunnelling process between the excited Cr3+ and the polaron state at the next-nearest-neighbour Nb-Nb(5+).
|Keywords:||lithium-niobate, defect structures, ions, Optics. Light, Physics and Astronomy(all), Physics and Astronomy (miscellaneous)|
|Subjects:||Science > Physics > Optics. Light|
|Department:||Faculty of Science > Physics|
|Depositing user:||Pure Administrator|
|Date Deposited:||21 Jun 2011 12:18|
|Last modified:||04 May 2016 18:24|