OBSERVATION OF PERIODIC, QUASI-PERIODIC AND CHAOTIC LOCALIZED EXCITATIONS IN NONLINEAR DIATOMIC MACRO-LATTICE

In one-dimensional damped and parametrically excited diatomic macro-la ttice, some kinds of recurrences for localized envelope excitations ar e observed. When drive frequency is 3.40 Hz and drive amplitude lies b etween 0.43 mm (the lower cutoff value) and 0.52 mm, the acoustic lowe r cutoff soliton mode is quite stable. As the drive amplitude increase s to 0.52 mm similar to 0.55 mm under the same drive frequency, the am plitude of the soliton changes periodically and/or quasiperiodically. For larger drive amplitude A(c) (0.55 mm < A(c) < 0.76 mm), the recurr ence of the soliton amplitude becomes chaotic. Finally if the drive am plitude exceeds the upper cutoff value, similar to 0.76 mm, the locali zed structure is totally destroyed.