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Results from measuring the angular dependence of magnetoresistance (MR) on the [La.sub.0.7][Ca.sub.0.3]Mn[O.sub.3] (LCMO] biepitaxial step junctions (BSJs) obtained by depositing LCMO film onto SrTiO3(100) substrate partially buffered with a layer of anatase TiO2(001) is reported. The magnetudes of anisotropic magnetoresistance (AMR) suggest that the conventional spin-orbit coupling effect, though may explain the in-plane anisotropy is inadequate to account for the perpendicular anisotropy.

A free-space electrooptic procedure is used to examine characteristics of photogenerated tetrahertz radiation from a superconducting YBa[subscript2]Cu[subscript 3]O[subscript 7-delta] (YBCO) bow-tie antenna.

A two-zone off-axis radio frequency (RF)-sputtering technique was utilized in developing Tl-based superconducting thin films in-situ. An ex-situ two zone post-annealing scheme analyzed the influence of Tl2O partial pressure on the growth and phase formation of several Tl-based superconducting phases. The RF-sputtering approach employs heating facilities for controlling the temperatures of the Tl2O3 source and substrate.

Magnetic field features of the combined function bending magnet with dipole and quadrupole field components are essential for the successful operation of the electron beam trajectory. These fields also dominate the photon beam quality. The vertical magnetic field [B.sub.y](x, y) calculation is performed by a computer code 'MAGNET' at the magnet center(s = 0). Those results are compared with the 2-D field measurement by the Hall probe mapping system. Also detailed survey has been made of the harmonic field strength and the main features of the fundamental integrated strength, effective length, magnetic symmetry, tilt of the pole face, offset of the field center and the fringe field. The end shims that compensate for the strong end negative sextupole field to increase the good field region for the entire integrated strength are discussed. An important physical feature of this combined function bending magnet is the constant ratio of dipole and quadrupole strength [integral of] Bds/[integral of] Gds which is expressed as a function of excitation current in the energy range 0.6 to 1.5 GeV.

The effect of the tilt angle of the bicrystal boundaries on the critical current and thermal properties of microwave-enhanced YBCO bicrystal weak-links is investigated by means of a standard four-probe measurement technique. No significant microwave enhancement is observed in YBCO weak-links with small grain boundary tilt angles. On the other hand, significant critical current density and critical temperature improvements are observed when the tilt angle is increased from 36.8 degrees to 45 degrees.

A new method of preparing phase pure, c-axis oriented TlBa2Ca2Cu3O9 thin films via dc sputtering is discussed. Based on the crucial role played by annealing thermodynamics and growth kinetics of the phase formation stage, it combines re-deposition and multi-step post-annealing to improve the surface morphology. To date, it has yielded films with a critical current density of 10,000,000 A/cm2 at 77 K with a zero-resistance transition temperature above 110 K.

A systematic study concerning the manifestation of dominant pinning mechanisms in laser ablated yttrium barium copper oxide (YBCO) films was conducted. Experiments involved the measurement of the direct transport critical current density of high quality Y1Ba2Cu3O7 superconducting thin films. Results indicate that the behavior of the pinning in the mixed-state of YBCO films is dependent to the growth orientation of the film and to the applied field configuration.

The studies related to the magnetism-induced ferroelectricity in the E-type orthorhombic HoMn[O.sub.3] (o-HMO) films grown on Nb-doped and undoped SrTi[O.sub.3](001) substrates is presented. The temperature dependent magnetization in the films is observed to exhibit an antiferromagnetic ordering around 44 K and an anomalous second magnetic ordering along the c-axis near 35 K.

Ultrafast optical pump-optical probe spectroscopy is used for probing the polaron dynamics in [La.sub.0.7][Ca.sub.0.3]Mn[O.sub.3] (LCMO) thin films. The results have shown that the fast photoinduced reflectivity change is due to the photoexcitation and trapping process of correlated Jahn-Teller polarons in the paramagnetic and ferromagnetic phases, thus implying the presence of electronic inhomogeneity in LCMO manganites.

The magnetotransport properties of both the [La.sub.0.625][Ca.sub.0.375]Mn[O.sub.3] (LCMO) and [La.sub.0.375][Pr.sub.0.25][Ca.sub.0.375]Mn[O.sub.3] (LPCMO) films are compared as a function of applied field at several characteristic temperatures. The results have shown that the persistent magnetic memory effect (PMME) phenomenon in LPCMO is due to the size distribution of the coexisting phases and in LCMO, the phase transition between paramagnetic and ferromagnetic is like an isomorphic transition in pure materials.

Pulsed laser deposition on SrTi[O.sub.3](110), LaAl[O.sub.3](110), and SrTi[O.sub.3](001) substrates are used for obtaining orthorhombic YMn[O.sub.3] thin films with (200), (020), and (001) orientations. The results from the analysis provide insight into the origin of the observed second reordering that might be due to some strain-induced canted antiferromagnetic (AFM) state instead of the incommensurate lock-in transitions.