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We have grown a-axis oriented YBa2Cu3O7−y (YBCO) films on LaSrGaO4 (LSGO) (100) substrates with (100) oriented seed layer of PrBa2Cu3O7−x (PBCO) using a pulsed laser deposition technique. PBCO films on LSGO (100) deposited even at ∼800 °C exhibits the a-axis orientation. In this temperature range, PBCO films on SrTiO3 (100) substrate exhibits the c-axis orientation. The YBCO film with a-axis orientation was grown on this PBCO(100) layer at a wide range of 650–800 °C. The YBCO films on PBCO free substrates have, on the other hand, c-axis orientation normal to the surface of the LSGO (100). We found that the preferred orientations of YBCO thin films can be controlled by the presence of PBCO films on LSGO substrate. For the a-axis orientated YBCO films, the resistance perpendicular to the c axis is 1/2 of that parallel to the c axis, suggesting the preferred orientation of c axis along the surface. The zero resistance superconducting transition temperature (Tc) of the films on the LSGO (100) and PBCO (100)/LSGO (100) substrates are 88.0 and 89.0 K, respectively.

As-grown YBa2Cu3O7−y (YBCO) thin films of 70 nm thickness have been prepared on LaSrGaO4(001), (100), and (110) single-crystal substrates at 700 °C using ArF laser ablation deposition. The c-axis oriented thin films with smooth surface morphology are obtained on LaSrGaO4 (001) and (100) substrates. The zero resistance temperatures (Tc) of the films on the (001) and (100) substrates are 90.0 K, and 88.1 K, respectively. On the (110) substrate, (110) YBCO planes grow epitaxially. The resistance perpendicular to the c axis in this film is 1/3 of that parallel to the c axis, showing Tc⊥=85.9 K and Tc∥=84.4 K, respectively. These results suggest that a LaSrGaO4 substrate having a low dielectric constant is an excellent substrate for the epitaxial growth and device application of high-Tc YBa2Cu3O7−y superconducting films.

This paper has described a technique of calculating voltage and power flow state of a distribution system using the information measured with two or more switches with sensors installed in a distribution system. The proposed technique is that, a set of the power distribution section where two or more switches with a sensor are connected is defined as the large section, and the active power and reactive power consumption in the large section are calculated based on measurement information, voltage (RMS), current (RMS) and power factor. Using the simple distribution system model that consisted of the large sections, the power consumption of the large section is calculated by the power flow calculation to separating power consumption and power distribution loss. It is distributed to the small sections that constitute the large section, and detailed power flow calculation is performed. Verification of the proposal technique and basic estimation of the calculation error were performed using the simple power distribution system model.

As candidates for functional layers, 3d transition metal oxides with perovskite structures show some interesting properties, such as ferromagnetism, ferroelectricity and superconductivity. Accordingly, combinations of these properties can be used to create new tunable microwave devices. Ferromagnetic/ferroelectric/superconducting multistructures, such as La0.70Sr0.30MnO3 (LSMO)/Pb(Zr0.52Ti0.48)O3 (PZT)/YBa2Cu3O7-y (YBCO) and YBCO/PZT/LSMO, have been fabricated by ArF excimer laser deposition on LaSrGaO4 (LSGO) [001] and (La0.30Sr0.70)(Al0.65Ta0.35)O3 (LSAT) [001] substrates. The resulting trilayer films have a highly c-axis oriented structure. Epitaxial YBCO films formed on PZT/LSMO//LSAT have a zero-resistance temperature of 87 K. Moreover, D-E and M-H hysteresis loop are observed for the LSMO/PZT/YBCO//LSGO structure using a conventional Sawyer-Tower circuit and a superconducting quantum interference device (SQUID). The remanent polarization and coercive field of the PZT layer are found to be 19 µC cm-2 and 275 kV cm-1 at 70 K, respectively. The remanent magnetic moment and coercive magnetic field are about 2.6 µB/site and 50 Oe respectively at 78 K. Furthermore, the microwave surface resistance (RS) (22 GHz) of the YBCO film in the YBCO/PZT/LSMO structure was 1.32 m at 77 K. These results suggest that LSMO/PZT/YBCO structures are favourable for use in superconducting microwave applications such as tunable phaseshifters and filters.

The ArF excimer laser deposition technique has been used to fabricate bioceramic hydroxyapatite (HAp) thin films on polymer materials such as polyimides (PI), polytetrafluoroethylene (PTFE), silicone rubber (SR), and polyethyleneterephthalate (PET). The crystallinity, structure, composition and surface morphology of HAp films are evaluated by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX) and atomic force microscopy (AFM). Crystallized HAp films are obtained on PI and PTFE, and mechanical properties of HAp films on the polymer materials are examined using an Instron testing machine. This result is very important to enable the application of organic/inorganic-ceramic composite materials in medical fields.