Superconducting quantum interference filters consisting of Josephson junctions with unconventional current-phase relation

Superconducting quantum interference filters (SQIFs) are parallel or serial Josephson junction arrays with a unique DC voltage output around vanishing magnetic field B = 0. Certain features of the voltage output also depend on the current-phase relation of the individual junctions in the array. Taking into account the first two harmonics I_c1 and I_c2 of the supercurrent we investigate the DC voltage output of the array. In particular we describe a characteristic magnetic field asymmetry of the voltage output. Applications of the theory include the design of SQIFs with novel flux to voltage transfer functions using high-T_c superconductors on bi- or tri-crystal substrates.