Topological acoustics in coupled nanocavity arrays

M Esmann,A Lemaître,N D Lanzillotti-Kimura,F R Lamberti

doi:10.1103/physrevb.98.161109

Abstract

The Su-Schrieffer-Heeger (SSH) model is likely the simplest one-dimensional concept to study non-trivial topological phases and topological excitations. Originally developed to explain the electric conductivity of polyacetylene, it has become a platform for the study of topological effects in electronics, photonics and ultra-cold atomic systems. Here, we propose an experimentally feasible implementation of the SSH model based on coupled one-dimensional acoustic nanoresonators working in the GHz-THz range. In this simulator it is possible to implement different signs in the nearest neighbor interaction terms, showing full tunability of all parameters in the SSH model. Based on this concept we construct topological transition points generating nanophononic edge and interface states and propose an easy scheme to experimentally probe their spatial complex amplitude distribution directly by well-established optical pump-probe techniques.

Highlights

The polymer trans-polyacetylene consists of a carbon chain with alternating C-C single and double bonds
The particular importance of the SSH model lies in its ability to provide a simple, yet prototypical example of topological phase transitions in one dimension
Ultracold atomic quantum gases in optical lattices [7] have been used for the direct measurements of Zak phases [8], for the observation of topological edge states [9], and for topological charge pumping [10,11]

Summary

Topological acoustics in coupled nanocavity arrays

We propose an experimentally feasible implementation of the SSH model based on coupled one-dimensional acoustic nanoresonators working in the gigahertz-terahertz range. In this simulator it is possible to implement different signs of the nearest-neighbor interaction terms, showing full tunability of all parameters in the SSH model. Based on this concept we construct topological transition points generating nanophononic edge and interface states and propose an easy experimental scheme to directly probe their spatial complex amplitude distribution by well-established optical pump-probe techniques

INTRODUCTION

Published by the American Physical Society

RESULTS AND DISCUSSION

CONCLUSIONS AND OUTLOOK