Li admixture greatly enhances n-type photoconductivity of KTaO3 crystals. Thermally stimulated current experiments indicate that this phenomenon is related with the presence of hole-trapping levels with depths of 50 - 100 meV. This is in good agreement with recent energy structure calculations showing the existence of levels at these energies above the top of the VB, due to perturbed O2- p-states. The study of visible photoluminescence and thermoluminescence shows that the hole-trapping centre also controls the emission process. We conclude in favour of radiative recombination involving O--Ta(4+)polaron pairs.

Photoinduced phenomena and shallow levels in K1-xLixTaO3

GIULOTTO, ENRICO VIRGILIO;GALINETTO, PIETRO;SAMOGGIA, GIORGIO;
2001

Abstract

Li admixture greatly enhances n-type photoconductivity of KTaO3 crystals. Thermally stimulated current experiments indicate that this phenomenon is related with the presence of hole-trapping levels with depths of 50 - 100 meV. This is in good agreement with recent energy structure calculations showing the existence of levels at these energies above the top of the VB, due to perturbed O2- p-states. The study of visible photoluminescence and thermoluminescence shows that the hole-trapping centre also controls the emission process. We conclude in favour of radiative recombination involving O--Ta(4+)polaron pairs.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11571/8010
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact