Convective and Absolute Eckhaus Instability Leading to Modulated Waves in a Finite Box

Nicolas B. Garnier (1) , Arnaud Chiffaudel (1) , François Daviaud (1, 2)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 SPHYNX - Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes

We report experimental study of the secondary modulational instability of a one-dimensional nonlinear traveling wave in a long bounded channel. Two qualitatively different instability regimes involving fronts of spatio-temporal defects are linked to the convective and absolute nature of the instability. Both transitions appear to be subcritical. The spatio-temporal defects control the global mode structure.

Domains: Physics [physics]

Nicolas B. Garnier, Arnaud Chiffaudel, François Daviaud. Convective and Absolute Eckhaus Instability Leading to Modulated Waves in a Finite Box. Physical Review Letters, 2002, 88, pp.134501. ⟨10.1103/PhysRevLett.88.134501⟩. ⟨cea-01373861⟩