Fibonacci-Engineered Spin and Charge Thermoelectrics in a Long Range Su-Schrieffer-Heeger Chain: A Pathway to Giant Figure of Merit

TL;DR

This paper explores how Fibonacci-modulated aperiodic SSH chains can significantly enhance spin and charge thermoelectric efficiency, revealing new pathways for designing advanced thermoelectric materials with high figure of merit.

Contribution

It introduces a novel Fibonacci-type aperiodic modulation in an extended SSH model to boost spin and charge thermoelectric performance, demonstrating a significant increase in the figure of merit.

Findings

Enhanced thermoelectric figure of merit ZT for charge and spin channels.

Distinct advantages in spin thermoelectric response.

Influence of aperiodic Fibonacci modulation on transport properties.

Abstract

In this work, we present a novel investigation into the spin-dependent thermoelectric performance of an extended Su-Schrieffer-Heeger (SSH) model, showcasing for the first time how its intrinsic spin filtration mechanism can be strategically harnessed to function as an efficient spin thermoelectric generator. By introducing a Fibonacci-type aperiodic modulation in the onsite energies, we engineer a deterministic disorder that mimics realistic aperiodic systems and profoundly influences transport characteristics. Furthermore, we incorporate both nearest-neighbor (NN) and next-nearest-neighbor (NNN) hopping amplitudes with tunable cosine dependencies, enabling us to meticulously explore the intricate interplay between these hopping processes and its implications on thermoelectric behavior. Our analysis reveals a remarkable enhancement in the dimensionless thermoelectric figure of merit ZT for both charge and spin transport channels, under carefully optimized conditions. Notably, the spin thermoelectric response exhibits distinct advantages, opening a new frontier in the design of next-generation thermoelectric materials and devices. This qualitative study not only deepens our understanding of aperiodic topological systems but also establish a foundational framework for exploiting spin-based thermoelectricity in low-dimensional platforms.