A combined experimental and computational investigation of coupling between polarization and epitaxial strain in highly polar ferroelectric PbZr(0.2)Ti(0.8)O3 (PZT) thin films is reported. A comparison of the properties of relaxed (tetragonality c/a approximately 1.05) and highly strained (c/a approximately 1.09) epitaxial films shows that polarization, while being amongst the highest reported ...

Interfacial strain gradients in oxide epitaxial thin films provide an interesting opportunity to study flexoelectric effects and their potential applications. Oxide epitaxial thin films can exhibit giant and tunable flexoelectric effects, which are six or seven orders of magnitude larger than those in conventional bulk solids. The strain gradient in an oxide epitaxial thin film can generate an ...

We report generation of ballistic electric currents in unbiased epitaxial graphene at 300 K via quantum interference between phase-controlled cross-polarized fundamental and second harmonic 220 fs pulses. The transient currents are detected via the emitted terahertz radiation. Because of graphene's special structure symmetry, the injected current direction can be well controlled by the polariza...

As the Si counterpart of graphene, silicene may be defined as an at least partially sp2-hybridized, atom-thick honeycomb layer of Si that possesses π-electronic bands. Here we show that two-dimensional, epitaxial silicene forms through surface segregation on zirconium diboride thin films grown on Si wafers. A particular buckling of silicene induced by the epitaxial relationship with the diborid...

Title of Document: ORIENTATION DEPENDENCE OF THE PIEZOELECTRIC PROPERTIES OF EPITAXIAL FERROELECTRIC THIN FILMS Jun Ouyang, Doctor of Philosophy, 2005 Directed By: Professor Alexander. L. Roytburd Dept. of Materials Science and Engineering There are both intrinsic piezoelectric response and extrinsic piezoelectric response in ferroelectric materials. The intrinsic piezoelectric response is due ...

The ability to control the microstructures and physical properties of hetero-epitaxial functional oxide thin films and artificial structures is a long-sought goal in functional materials research. Normally, only the lattice misfit between the film and the substrate is considered to govern the physical properties of the epitaxial films. In fact, the mismatch of film unit cell arrangement and the...

The preparation of a YBa2Cu3O7−x/LaNiO3/YBa2Cu3O7−x sandwich structured film on a LaAlO3 (100) substrate by a sol-gel method was investigated. YBa2Cu3O7−x/LaNiO3/YBa2Cu3O7−x tri-layer heterostructures with different epitaxial characteristics can be deposited by controlling the heat treatment temperature. X-ray diffraction and transmission electron microscopy results show that the bottom YBCO fi...

The formation of ordered arrays of molecules via self-assembly is a rapid, scalable route towards the realization of nanoscale architectures with tailored properties. In recent years, graphene has emerged as an appealing substrate for molecular self-assembly in two dimensions. Here, the first five years of progress in supramolecular organization on graphene are reviewed. The self-assembly proce...

UNLABELLED Epitaxial heterostructures combining ferroelectric (FE) and ferromagnetic (FiM) oxides are a possible route to explore coupling mechanisms between the two independent order parameters, polarization and magnetization of the component phases. We report on the fabrication and properties of arrays of hybrid epitaxial nanostructures of FiM NiFe(2)O(4) (NFO) and FE PbZr(0.52)Ti(0.48)O(3) o...

Epitaxial Pt(001) thin films have been grown on MgO(001) substrates using dc magnetron sputtering with an Ar/0 2 mixture at 700'C. The width (FWHM) of the rocking curve of the Pt(002) peak is between 0.160 and 0.200, which is only 0.05' wider than that of the MgO (002) peak of the cleaved substrate. The film surface roughness is about 1 nm (rms) for a 240 nm thick Pt film. No grain structure co...