AC Losses and Magnetic Coupling in Multifilamentary 2G HTS Conductors and Tape Arrays

Striation of coated HTS conductors is a promising way of reducing their ac loss. In particular, loss in the striated conductors is affected by magnetic coupling between the superconducting filaments. We experimentally study the in-field behavior of the planar arrays of superconducting tapes and deduct contribution of such coupling to the net ac loss. This contribution is largest at lowest ac field amplitudes. Dependence of the loss upon the inter-filament separation is studied and results are compared to the existing theoretical models and numerical simulations. We show that magnetization ac loss of practical multi-filamentary conductors can be reasonably fitted with the theoretical result of Mawatari for infinite arrays of magnetically-coupled superconducting strips.