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Two high-temperature superconducting (HTS) coils are fabricated that simulate the windings of a HTS traction transformer for railroad rolling stock.

A study was conducted on the fabrication and testing of high temperature superconducting (HTS) current leads designed for a 1kWh/1MW module type superconducting magnetic energy storage system. Bulk HTS were employed to minimize the current leads' heat load. Test results of prototype leads reveal a 0.035 W heat load in steady state at 1 kA rated current and 0.05 g/s rated flow rate.

A design study was conducted on high temperature superconducting (HTS) current leads for application in a 11kWh/1MW module type superconducting magnetic energy storage system. Bulk HTS were employed to minimize the current leads' heat load. An optimal design was developed for HTS current leads that can accommodate less than 01.W heat load at the cold-end terminal.

A superconducting magnet system has been designed and constructed for a 1-MW gyrotron operating at frequencies between 110 GHZ and 140 GHz. Aside from superconducting magnets, it is composed of a cryostat, power supplies, a two-stage cooler. The latter is used to minimize the thermal load of liquid helium. Tests with a 5.0-T magnetic field in the resonance region of its superconducting split coil confirm the validity of the design.

Capacitance-voltage (C-V) characteristics of a Si/C&sub60; heterojunction, i.e., a HF solution (7.3% HF+30% NH[sub 4]F) treated Si surface interfaced solid crystal of C&sub60; molecules, were measured while applying various ac frequencies. The entire C[sub 60] thin film and near-interface region of the Si wafer behaved as a depletion region, with the C – V curve showing two distinct regions: one above and one below a threshold bias voltage. Below the threshold, C –V characteristics were dependent on applied frequency, which suggests the presence of interface states that only affect capacitance at lower frequencies. This frequency dependence was analyzed by assuming a suitable equivalent circuit, and based on derived curve-fitting circuit parameters the interface states density was accordingly estimated to have a value as low as ∼ 10[sup 11]/cm² eV. Such a small density indicates that only a few lattice defects occur within the interface of the HF-treated Si surface and C&sub60; crystal. Although no frequency dependence was observed above the threshold, the C – V characteristics were found to be dependent on the width of the depletion region in Si. [ABSTRACT FROM AUTHOR]