The variation of PbTiO.sub.3./sub. bandgap at ferroelectric phase transition

0465090 - FZÚ 2017 RIV GB eng J - Článek v odborném periodiku
Železný, Vladimír - Chvostová, Dagmar - Šimek, Daniel - Máca, František - Mašek, Jan - Setter, N. - Huang, Y.H.
The variation of PbTiO₃ bandgap at ferroelectric phase transition.
Journal of Physics-Condensed Matter. Roč. 28, č. 2 (2016), 1-8, č. článku 025501. ISSN 0953-8984. E-ISSN 1361-648X
Grant CEP: GA ČR(CZ) GAP204/11/1011
Institucionální podpora: RVO:68378271
Klíčová slova: band gap * ellipsometry * ferroelectrics
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 2.678, rok: 2016

Optical properties of the PbTiO3 thin films fabricated by chemical solution deposition have been measured with variable angle spectroscopic ellipsometry in the spectral range of 1–6 eV functions and band gap energy were determined in the whole temperature range. The direct band gap varies from the value 3.88 eV at room temperature to the value 3.67 eV just above the phase transition. The temperature dependence of the film lattice parameters was also measured by x-ray and it shows a strong correlation with the band gap. The comparison of experimental data with ab initio electronic structure calculations simulating the temperature development of dielectric function and band gap is also presented.
Trvalý link: http://hdl.handle.net/11104/0263807