resumo
This work is devoted to disclosing the effect of epitaxial strain on crystallographic, transport, and nonlinear optical properties of a bilayer structure consisting of one ferroelectric (FE) (BaTiO3 with a thickness of 4 nm) and one ferromagnetic (La0.7Ca0.3MnO3 with the thickness of 12 nm) layers. Both tensile (of about similar to 6% caused by the MgO substrate) and compressive (of about similar to 1% caused by the SrTiO3 substrate) strains reduce the bulk metal-to-insulator phase transition temperature of the La0.7Ca0.3MnO3 layer from 240 K towards 195 K and 160 K, respectively. The appearance of the effect of colossal electroresistance, linear and nonlinear current-voltage behaviours and contribution of FE polarization switching in the BaTiO3 layer to the conductivity are associated with the influence of epitaxial strain. The predominance of the compressive over the tensile strain leads to the hysteresis behaviour of electroresistance, maximum conductivity caused by the resonant-tunnelling mechanism, and strong nonlinear optical dependence on the applied electric field.
categoria
Physics, Applied
autores
Ivanov, MS; Buryakov, AM; Vilarinho, PM; Mishina, ED
nossos autores
Maxim Ivanov
Investigador Júnior
Paula Maria Lousada Silveirinha Vilarinho
Vice-Diretoragradecimentos
The central part of this work (samples development, fabrication, and characterization using all described methods) was supported by the Russian Science Foundation (Grant No. 20-79-10223). The Fundacoao para a Ciencia e Tecnologia (FCT) through the project BIOMEMs (POCI-01-0145-FEDER-032095) is also acknowledged.