相关论文: Structural phase transitions in epitaxial perovski…
It has been well established that both in bulk at ambient pressure and for films under modest strains, cubic SrCoO$_{3-\delta}$ ($\delta < 0.2$) is a ferromagnetic metal. Recent theoretical work, however, indicates that a magnetic phase…
Transition metal oxide thin films show versatile electrical, magnetic, and thermal properties which can be tailored by deliberately introducing macroscopic grain boundaries via polycrystalline solids. In this study, we focus on the…
The strain dependent functional properties of epitaxial transition metal oxide films can be significantly modified via substrate selection. However, large lattice mismatches preclude dislocation-free epitaxial growth on ferroelectric…
We analyze X-ray diffraction data used to extract cell parameters of ultrathin films on closely matching substrates. We focus on epitaxial La2/3Sr1/3MnO3 films grown on (001) SrTiO3 single crystalline substrates. It will be shown that, due…
Electronic transport has been investigated for strong spin-orbit coupled perovskite SrIrO3 thin films grown at various substrate temperatures. The electronic transport of the SrIrO3 films is found to be very sensitive to the growth…
Reversible topotactic transitions between oxygen-vacancy-ordered structures in transition metal oxides provide a promising strategy for active manipulation of material properties. While transformations between various oxygen-deficient…
A thermodynamic theory is developed for dense laminar domain structures in epitaxial ferrolectric films. It is found that, at some critical misfit strain between the film and substrate, the 90 degrees c/a/c/a domain structure becomes…
The effect of layer-by-layer heterostructuring and epitaxial strain on lattice instabilities and related ferroelectric properties is investigated from first principles for the [001]-(PbTiO$_3$)$_1$(PbZrO$_3$)$_1$ superlattice and pure…
SrVO3 and SrNbO3 are perovskite-type transition-metal oxides with the same d1 electronic configuration. Although SrNbO3 (4d1) has a larger d orbital than SrVO3 (3d1), the reported electrical resistivity of SrNbO3 is much higher than that of…
We present the temperature- and thickness-dependent structural and morphological evolution of strain induced transformations in highly-strained epitaxial BiFeO3 films deposited on LaAlO3 (001) substrates. Using high-resolution X-ray…
The structure and microstrucutre of fully-strained BiCrO3 thin films have been investigated by X-rays diffraction and transmission electron microscopy, at room temperature. Interestingly, three structural variants are simultaneously…
The subtle balance of electronic correlations, crystal field splitting and spin--orbit coupling in layered Ir$^{4+}$ oxides can give rise to novel electronic and magnetic phases. Experimental progress in this field relies on the synthesis…
Oxide electronics relies on the availability of epitaxial oxide thin films. The extreme flexibility of the chemical composition of ABO3 perovskites and the broad spectrum of properties they cover, inspire the creativity of scientists and…
Lattice structure can dictate electronic and magnetic properties of a material. Especially, reconstruction at a surface or heterointerface can create properties that are fundamentally different from those of the corresponding bulk material.…
Domain structures of 320 nm thin epitaxial films of ferroelectric PbTiO3 grown by MOCVD technique in identical conditions on SmScO3 and TbScO3 perovskite sub- strates have been investigated by Raman spectroscopy and piezoresponse force…
The strain dependence of electric and magnetic properties has been widely investigated, both from a fundamental science perspective and an applications point of view. Electromechanical coupling through field-induced polarization rotation…
We demonstrate that SrRuO3 and CaRuO3 thin films undergo a room temperature structural phase transition driven by the substrate imposed epitaxial biaxial strain. As tensile strain increases, ARuO3 (A=Ca, Sr) films transform from the…
The structural evolution of a polydomain ferroelectric Pb(Zr0.2Ti0.8)O3 film was studied by temperature dependent X-ray diffraction. Two critical temperatures were evidenced: T*=740K, corresponding to a change in the domain structure…
We investigate the variation of the spontaneous ferroelectric polarization with epitaxial strain for BaTiO$_3$, PbTiO$_3$, LiNbO$_3$, and BiFeO$_3$ using first principles calculations. We find that while the strain dependence of the…
We report first-principle atomistic simulations on the effect of local strain gradients on the nanoscale domain morphology of free-standing PbTiO$_3$ ultrathin films. First, the ferroelectric properties of free films at the atomic level are…