Structural characteristics of phase transformations in epitaxial ferroelectric films are analyzed via a Landau–Devonshire thermodynamic formalism. It is shown that the phase transformation temperature, the lattice parameters, and the order of the phase transformation are a strong function of the misfit strain and are considerably different compared to unconstrained, unstressed single crystals o...

The anomalous Hall effect (AHE) in the reactively sputtered epitaxial and polycrystalline γ'-Fe4N films is investigated systematically. The Hall resistivity is positive over the entire temperature range. The magnetization, carrier density and grain boundary scattering have a major impact on the AHE scaling law. The scaling exponent γ in the conventional scaling of ρAH ∝ ρ(γ)(xx) is larger than ...

IN THE MIDST OF THE EPITAXIAL CIRCUITRY REVOLUTION IN SILICON TECHNOLOGY, WE LOOK AHEAD TO THE NEXT PARADIGM SHIFT: effective use of the third dimension - in particular, its combination with epitaxial technology. We perform ab initio calculations of atomically thin epitaxial bilayers in silicon, investigating the fundamental electronic properties of monolayer pairs. Quantitative band splittings...

Paths of tetragonal states between two phases of a material, such as bcc and fcc, are called Bain paths. Two simple Bain paths can be defined in terms of special imposed stresses, one of which applies directly to strained epitaxial films. Each path goes far into the range of nonlinear elasticity and reaches a range of structural parameters in which the structure is inherently unstable. In this ...

We have grown a novel epitaxial phase of cerium on vanadium using molecular-beam epitaxy and characterized by high-energy electron and x-ray diffraction. The results show that the Ce phase is contracted by 8% in the basal plane and expanded 2% out of the plane when compared to the ambient-temperature and ambient-pressure fcc, y-Ce. Furthermore, the relative orientation of the Ce(111) and the V(...

Direct observations using scanning transmission electron microscopy unveil an intriguing interfacial bi-layer that enables epitaxial growth of a strain-free, monoclinic, bronze-phase VO2(B) thin film on a perovskite SrTiO3 (STO) substrate. We observe an ultrathin (2-3 unit cells) interlayer best described as highly strained VO2(B) nanodomains combined with an extra (Ti,V)O2 layer on the TiO2 te...

IMR KINKEN Research Highlights 2012 Orthorhombic barium disilicide (BaSi2) has been proposed as a promising, novel candidate for high-efficiency thin-film solar cells owing to its large absorption coefficient of 105 cm-1 at 1.5 eV [1] and bandgap that is tunable to 1.4 eV by substituting half of the Ba sites with isoelectronic Sr atoms [2]. A base layer only 1 μm thick is considered sufficient ...

In this work, we describe the homoand hetero-epitaxial growth of hexagonal and cubic MgxZn1−xO thin films on lattice matched substrates of c-Al2O3, ZnO, MgO and SrTiO3. The crystalline quality, composition and epitaxial nature of the alloy films are obtained by x-ray diffraction and Rutherford backscattering spectroscopy (RBS) techniques. The RBS channeling yields are in the range 3–8% for homo...

*Correspondence: Ram K. Gupta, Department of Chemistry, Pittsburg State University, 1701 South Broadway, Pittsburg, KS-66762, USA e-mail: [email protected] Epitaxial tin ferrite (SnFe2O4) thin films were grown using KrF excimer (248 nm) pulsed laser deposition technique under different growth conditions. Highly epitaxial thin films were obtained at growth temperature of 650°C. The quality a...

We performed total energy calculations on strained tetragonal states of bulk fcc palladium by means of density functional theory using the local density approximation. Coherent epitaxial growth of thin films on cubic (001) substrates results in such strained structures due to heteroepitaxy with mismatch. We obtained what is called the epitaxial Bain path of palladium, a structural transition be...