Inter-balloon mode interactions due to a secondary instability: periodic and quasi-periodic spatial superstructures

This paper investigates the excitation and interaction of modes from multiple instability balloons with considerably different instability thresholds. This work shows that the excitation of these modes from balloons with higher instability thresholds is made possible due to a secondary instability of the fundamental ones that are born from the balloon of the lowest instability threshold. This study explains the formation of periodic and quasi-periodic spatial structures observed numerically through a secondary bifurcation analysis. Results of analysis agree well with numerical results.