Properties of the interface of Ba<inf>0.8</inf>Sr<inf>0.2</inf>TiO<inf>3</inf>/LaMnO<inf>3</inf> heterostructure

We investigate the properties of quasi-two-dimensional electron gas at the interface between ferroelectric oxide and insulating oxide in Ba0.8Sr0.2TiO3/LaMnO3 heterostructure after applying magnetic or electric fields. Interface conductivity was measured by a four-point probe method before and after the effect of an electric field on the Ba0.8Sr0.2TiO3 ferroelectric film. It is shown that the state with high conductivity can be turned off when a non-uniform electric field is applied to a ferroelectric film. Besides, the high conducting interface state can be turned on under the influence of a uniform electric field on the ferroelectric film

Investigation of an effect of electric field applied to ferroelectric film upon conductivity of quasi-two dimensional electron gas at the Ba<inf>0.8</inf>Sr<inf>0.2</inf>TiO<inf>3</inf>/LaMnO<inf>3</inf> interface

© 2020, © 2020 Taylor & Francis Group, LLC. We investigate the effect of electric field on the properties of quasi-two-dimensional electron gas at the interface between ferroelectric oxide and insulating oxide in Ba0.8Sr0.2TiO3/LaMnO3 (BSTO/LMO) heterostructure. Interface conductivity measurements were performed by a four-point probe method before and after the effect of electric field on Ba0.8Sr0.2TiO3 ferroelectric film. We have shown that when a non-uniform electric field is applied to a ferroelectric film, we can turn off the state with high conductivity. Whereas under the influence of a uniform electric field on the ferroelectric film, we can turn on the interface state of high conductivity

Thickness Dependence of the Properties of Epitaxial Barium Strontium Titanate Thin Films

International audienceHeteroepitaxial Ba (x) Sr1 - x TiO3 thin films of different thicknesses have been studied in the paraelectric phase at a temperature of 600A degrees C. The lattice parameters of the film have nonlinear dependence on the thickness. The misfit strain and unit cell volume increase with decreasing thickness. The behavior of the misfit strain with variations in the thickness is well described in the model of the double electric layer formed during the synthesis of the film at the interface with the substrate

Investigation of the barium strontium titanate films on the silicon substrate

A study of the electrical and photoelectric properties of the heterostructure of barium strontium titanate film on a silicon substrate was performed. The conductivity of the heterostructure significantly increased and the capacitance decreased with frequency. The photoconductivity significantly increased for the sample modified by Cr+ ion implantation. The temperature dependence of the resistance under green laser irradiation demonstrated maxima at 150 K

Thin ferroelectric Nd-doped BiFeO3 films with orthorhombic structure

International audienceX-ray diffraction and Raman spectroscopy of epitaxial Nd-doped bismuth ferrite films on MgO substrates reveal their orthorhombic symmetry Fmm2 (a = 7.914 Å, b = 7.913 Å, and c = 7.937 Å). © 2010 Allerton Press, Inc

Strain engineering of perovskite thin films using a single substrate

International audienceCombining temperature-dependent x-ray diffraction, Raman spectroscopy and firstprinciples-based effective Hamiltonian calculations, we show that varying the thickness of (Ba0.8Sr0.2)TiO3 (BST) thin films deposited on the same single substrate (namely, MgO) enables us to change not only the magnitude but also the sign of the misfit strain. Such previously overlooked control of the strain allows several properties of these films (e.g. Curie temperature, symmetry of ferroelectric phases, dielectric response) to be tuned and even optimized. Surprisingly, such desired control of the strain (and of the resulting properties) originates from an effect that is commonly believed to be detrimental to functionalities of films, namely the existence of misfit dislocations. The present study therefore provides a novel route to strain engineering, as well as leading us to revisit common belief