Disorder driven topological phase transitions in 1D mechanical quasicrystals

Abstract: We examine the transition from trivial to non-trivial phases in a Su-Schrieffer-Heeger model subjected to disorder in a quasi-periodic environment. We analytically determine the phase boundary, and characterize the localization of normal modes using their inverse participation ratio. We compute energy-dependent mobility edges and provide evidence for the emergence of a topological Anderson insulator within specific parameter ranges. Whereas the phase transition boundary is affected by the quasi-periodic modulation, the topologically insulating Anderson phase is stable with respect to the chiral disorder in a quasi-periodic setup. Additionally, our results also uncover a re-entrant topological phase transition from non-trivial to trivial phases for certain values of quasi-periodic modulation with fixed chiral disorder.