A current controlled delay in the time of flight of electrical picosecond pulses in a YBa2Cu3O7 spiral delay line has been investigated using optoelectronic sampling techniques. The transmission line is a microwave stripline on the LaAlO3 substrate and is passivated with the contact pads open. The measured delay time clearly shows a squared dependence on the applied current, in good agreement with Ginzburg–Landau theory for the case of a uniform current density through a thin film.

Only limited data are available on tritium release from irradiated Be. Few models have been suggested for tritium release from beryllium. Simple diffusion/desorption models have been proposed, but lack the capability of accounting for important phenomena such as burst release through interconnected porosity and the effect of the Be0 impurity layer. This paper describes the application of a new model for tritium release from Be, BETTY, to the analysis of recent experimental data. The model includes diffusion through Be and BeO, surface desorption and diffusion through interconnected porosity (as-fabricated or irradiation-induced). Tritium diffusion and desorption coefficients for Be and Be0 are estimated from the analysis and compared to previously estimated values.

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