Dielectric Substrate Dependence of Thermoelectric Transport in BLG-GaAs-BLG Heterostructures

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Van Tai, Vo, Van Tuan, Truong, Tai, Tran Trong, Dat, Le Tri, Vy, Nguyen Duy
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915427090694144
author Van Tai, Vo
Van Tuan, Truong
Tai, Tran Trong
Dat, Le Tri
Vy, Nguyen Duy
author_facet Van Tai, Vo
Van Tuan, Truong
Tai, Tran Trong
Dat, Le Tri
Vy, Nguyen Duy
contents We theoretically study the thermoelectric transport S in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al2O3, HfO2). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower S, and the thermopower of the materials is in the order of HfO2 > Al2O3 > h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering Sd decreases (increases) at low (high) densities versus equal densities, while acPE scattering Sg remains stable, making S largely Sg-dependent. Increasing interlayer distance d enhances S, while higher temperature boosts Sd (notably at low densities) with minimal effect on Sg. These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices
format Preprint
id arxiv_https___arxiv_org_abs_2508_03035
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Dielectric Substrate Dependence of Thermoelectric Transport in BLG-GaAs-BLG Heterostructures
Van Tai, Vo
Van Tuan, Truong
Tai, Tran Trong
Dat, Le Tri
Vy, Nguyen Duy
Mesoscale and Nanoscale Physics
We theoretically study the thermoelectric transport S in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al2O3, HfO2). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower S, and the thermopower of the materials is in the order of HfO2 > Al2O3 > h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering Sd decreases (increases) at low (high) densities versus equal densities, while acPE scattering Sg remains stable, making S largely Sg-dependent. Increasing interlayer distance d enhances S, while higher temperature boosts Sd (notably at low densities) with minimal effect on Sg. These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices
title Dielectric Substrate Dependence of Thermoelectric Transport in BLG-GaAs-BLG Heterostructures
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2508.03035