Observation of end-to-end pumping in a quasiperiodic Fibonacci-type photonic chain

TL;DR

This paper demonstrates end-to-end topological pumping in a quasiperiodic Fibonacci photonic chain through numerical simulations and experimental implementation, showing robustness against structural defects.

Contribution

It introduces a novel topological pump in a Fibonacci-type photonic lattice, combining theoretical modeling and experimental validation for robust state transfer.

Findings

Localized pumping state can be transferred with minimal structural change.

Experimental setup confirms theoretical predictions of light transfer.

Pumping remains robust against structural defects.

Abstract

Topological pumps offer a promising route to operate as connecting buses, supplying efficient and robust connectivity between non-neighboring elements in a network. Here, we investigate a finite quasiperiodic Fibonacci-type photonic chain and demonstrate its ability for end-to-end pumping, with only small and simple changes to the system. First, we use a tight-binding formalism to numerically show that a localized pumping state can be transferred between opposite ends of the system, with only a small structural change to the chain. Then, we experimentally implement this topological pump in an array of coupled optical waveguides, where light propagation is effectively described by the tight-binding model under the paraxial approximation, enabling direct correspondence between theory and experiment. We numerically simulate and experimentally demonstrate pumping by injecting light into a single waveguide at one end of the setup, which activates a localized pumping state. As the light propagates along the wave guide array, it is also pumped to the other end. We further show that pumping remains robust against structural deformation, such as controlled defects in the waveguide array. Our results establish that quasiperiodic Fibonacci-type photonic lattices are a robust and experimentally viable platform for disorder-resilient state transfer.