Phase locking of Josephson flux-flow oscillators in non-uniform microwave fields

Phase locking phenomena in Josephson flux-flow oscillators induced by non-uniform microwave fields are investigated both numerically and analytically. For low values of the amplitude of the microwave signal, a good agreement is found between analytical and numerical results. For odd phase locking steps, the agreement extends also to high amplitude values of the microwave signal. The discrepancy observed at high microwave amplitudes for even phase locking steps, is also discussed. (C) 2001 Published by Elsevier Science B.V.