Anomalous response, re-emerging localization-transition and robust corner sates in self-similar peano fractal

Abstract

Anomalous spectral response from the non-interacting electrons on a peano fractal is recorded within tight-binding framework. It is observed that a minimal off-diagonal anisotropy can modulate the transport characteristics of the lattice. Drastic modification in the nature of the eigenstates has been validated through the workout of level spacing statistics. Further, a two-dimensional quasiperiodic Aubry-André and Harper variation in the overlap integral can invite re-entrant localization-delocalization transition for the self-similar model. This is associated with the possible existence of single-particle mobility edge in the energy landscape. Our results are corroborated by the evaluation of inverse participation ratio, fractal dimension and quantum dynamical response. The spectrum is shown to formulate a quantum butterfly pattern with the frequency of the modulation. Chiral symmetry protected edge states are found to be insensitive with respect to moderate diagonal disorder.