Photoconductivity in LiNbO3 crystals codoped with MgO and Cr2O3

L. Arizmendi; C. De las Heras; F. Jaque; A. Suchocki; S. Kobyakov; T. P. J. Han

doi:10.1007/s00340-006-2520-7

Photoconductivity in LiNbO3 crystals codoped with MgO and Cr2O3

L. Arizmendi, C. De las Heras, F. Jaque, A. Suchocki, S. Kobyakov, T. P. J. Han

Research output: Contribution to journal › Article › peer-review

3 Citations (Scopus)

Abstract

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+).

Original language	English
Pages (from-to)	123-127
Number of pages	5
Journal	Applied Physics B: Lasers and Optics
Volume	87
Issue number	1
DOIs	https://doi.org/10.1007/s00340-006-2520-7
Publication status	Published - Mar 2007

Keywords

lithium-niobate
defect structures
ions

Access to Document

10.1007/s00340-006-2520-7

Cite this

@article{c3532d1e30994433894dc6ee7a1e2e9c,

title = "Photoconductivity in LiNbO3 crystals codoped with MgO and Cr2O3",

abstract = "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",

author = "L. Arizmendi and Heras, {C. De las} and F. Jaque and A. Suchocki and S. Kobyakov and Han, {T. P. J.}",

year = "2007",

month = mar,

doi = "10.1007/s00340-006-2520-7",

language = "English",

volume = "87",

pages = "123--127",

journal = "Applied Physics B: Lasers and Optics",

issn = "0946-2171",

number = "1",

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TY - JOUR

T1 - Photoconductivity in LiNbO3 crystals codoped with MgO and Cr2O3

AU - Arizmendi, L.

AU - Heras, C. De las

AU - Jaque, F.

AU - Suchocki, A.

AU - Kobyakov, S.

AU - Han, T. P. J.

PY - 2007/3

Y1 - 2007/3

N2 - 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+).

AB - 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+).

KW - lithium-niobate

KW - defect structures

KW - ions

U2 - 10.1007/s00340-006-2520-7

DO - 10.1007/s00340-006-2520-7

M3 - Article

VL - 87

SP - 123

EP - 127

JO - Applied Physics B: Lasers and Optics

JF - Applied Physics B: Lasers and Optics

SN - 0946-2171

IS - 1

ER -