# Probing one-dimensional topological phases in waveguide lattices with broken chiral symmetry

## TL;DR

This paper demonstrates that topological phases and quantized Zak phases can be observed in one-dimensional waveguide lattices with broken chiral symmetry by using continuous-time photonic quantum walks and beam displacement measurements.

## Contribution

It reveals that topological properties can be probed in systems lacking chiral symmetry, expanding the understanding of topological phases in photonic lattices.

## Key findings

- Quantized Zak phase detected in broken chiral symmetry systems
- Edge states partially protected by inversion symmetry
- Beam displacement measurements reveal topological phases

## Abstract

One-dimensional lattices with chiral symmetry are known to possess quantized Zak phase and nontrivial topological phases. Here it is shown that quantized Zak phase and nontrivial edge states, partially protected by inversion symmetry rather than chiral symmetry, can be observed and probed in the bulk exploiting continuous-time photonic quantum walk in zig-zag waveguide arrays. Averaged beam displacement measurements can detect quantized Zak phase and non-trivial topological phases in the extended Su-Schrieffer-Heeger model with broken chiral symmetry.