PHASE FRONT INSTABILITY IN PERIODICALLY FORCED OSCILLATORY SYSTEMS

Multiplicity of phase states within frequency locked bands in periodic ally forced oscillatory systems may give rise to front structures sepa rating states with different phases. A new front instability is found within bands where omega(forcing)/omega(system) = 2n (n > 1). Stationa ry fronts shifting the oscillation phase by pi lose stability below a critical forcing strength and decompose into n traveling fronts each s hifting the phase by pi/n. The instability designates a transition fro m stationary two-phase patterns to traveling n-phase patterns.