We have measured the Hall resistance in two-dimensional arrays of ultrasmal
l aluminium Josephson junctions. We found that the Hall resistance was peri
odical with respect to an external magnetic field applied perpendicular to
the plane of the array. We also found that the Hall resistance was affected
by an applied voltage to a nearby gate electrode, but not by a gate plane
silting underneath the array. (C) 2000 Elsevier Science B.V. All rights res
erved.