Mapping Topology-Localization Phase Diagram with Quasiperiodic Disorder Using a Programmable Superconducting Simulator

TL;DR

This study uses a programmable superconducting simulator to experimentally map the phase diagram of a 1D topological model with quasiperiodic disorder, revealing complex transitions among extended, critical, and localized states.

Contribution

First experimental mapping of the topology-localization phase diagram in a quasiperiodic 1D system using a superconducting simulator, uncovering rich phase behaviors and critical states.

Findings

Identification of trivial and topological phases with various bulk states

Observation of transitions from extended to localized to critical states with increasing disorder

Discovery of multifractality and self-similarity in critical states

Abstract

We explore topology-localization phase diagram by simulating one-dimensional Su-Schrieffer-Heeger (SSH) model with quasiperiodic disorder using a programmable superconducting simulator. We experimentally map out and identify various trivial and topological phases with extended, critical, and localized bulk states. We find that with increasing disorder strength, some extended states can be first replaced by localized states and then by critical states before the system finally becomes fully localized. The critical states exhibit typical features such as multifractality and self-similarity, which lead to surprisingly rich phases with different types of mobility edges and scaling behaviors on the phase boundaries. Our results shed new light on the investigation of the topological and localization phenomena in condensed-matter physics.