  We study experimentally and numerically the zero-voltage supercurrent vs.
magnetic field of non-uniform arrays of Josephson junctions parallel-connected
by a superconducting stripline. The measured curves are complex, unique and in
excellent agreement with numerical simulations using a specially developed
model. Using this, we can optimize the arrays to have any desired interference
pattern. Such new devices could find applications in magnetometry,
quasiparticle mixers and detectors, flux-flow oscillators and superconducting
electronics.
