The tetragonal states produced by isotropic pseudomorphic epitaxial strain in the ~001! plane on a tetragonal phase of a crystal are calculated for V, Ti, Rb, Li, K, and Sr from first-principles electronic theory. It is shown that each metal has two tetragonal phases corresponding to minima of the total energy with respect to tetragonal deformations ~and hence are equilibrium phases! and that t...

We have investigated the nanoscale switching properties of strain-engineered BiFeO(3) thin films deposited on LaAlO(3) substrates using a combination of scanning probe techniques. Polarized Raman spectral analysis indicates that the nearly tetragonal films have monoclinic (Cc) rather than P4mm tetragonal symmetry. Through local switching-spectroscopy measurements and piezoresponse force microsc...

The PZT material near the morphotropic phase boundary where a monoclinic phase was observed is studied in this paper. A theory of the tetragonal to monoclinic phase transition was developed within the Landau free energy approach. The order parameter is the electric polarization vector. The phase transition from the tetragonal to the monoclinic phase is of the first order near the second order. ...

The small exciton binding energy of perovskite suggests that the long-lived photoluminescence and slow recovery of the ground state bleaching of the tetragonal phase at room temperature results primarily from the decay of free charges rather than the decay of the initially created excitons. Here we demonstrate the ground state bleaching recovery of the orthorhombic phase of methylammonium lead ...

Abstract: Zirconia solid electrolytes with nonequilibrium composite structure were prepared by impregnation of a porous 8YSZ matrix with a solution of Zirconia. Microstructures were characterized by XRD and SEM. The electrical properties were studied by impedance spectroscopy as a function of temperature. Biaxial flexural strength and fracture toughness of composite samples were measured by rin...

a hydrothermal method for preparation of nano-size zirconia has been studied to optimize the effective parameters (precursor concentration, temperature and time) using response surface methodology (rsm). the synthesized zirconia samples were characterized through x-ray diffraction (xrd), scanning electron microscope (sem) and transmission electron microscopy (tem) analyses to identify mean nano...