Topological end state and enhanced thermoelectric performance of a supramolecular device

TL;DR

This study designs a supramolecular device based on SSH chains with topological end states, demonstrating enhanced thermoelectric performance and switch effects, promising for thermoelectric applications.

Contribution

Introduces a new supramolecular device with topological end states based on SSH chains, showing improved thermoelectric efficiency and switchability under various perturbations.

Findings

Achieves a ZT above 2 over a broad chemical potential range.

Topological end states significantly increase power factor.

System exhibits a prominent switch effect under perturbations.

Abstract

Supramolecular device (SMD) with topological end states and a noncovalent junction is rarely investigated but deemed promising for thermoelectric (TE) applications. We designed a new kind of SMD based on the Su-Schrieffer-Heeger (SSH) chains, and calculated TE properties of it using the non-equilibrium Green's function (NEGF) method. By scaling TE performance under different optimization conditions, we found the best scenario. Our result shows that the existing topological end states indeed give rise to a large value of power factor, rendering a dimensionless figure-of-merit ZT above 2 in a broad range of chemical potential (doping). Moreover, by imposing the system to various perturbations including end state shift, structural change and disorder, we found that the SMD system possesses a prominent switch effect, further optimizing its performance for TE applications.