Seebeck Coefficient of a Single van der Waals Junction in Twisted Bilayer Graphene

Abstract

When two planar atomic membranes are placed within the van der Waals distance, the charge and heat transport across the interface are coupled by the rules of momentum conservation and structural commensurability, leading to outstanding thermoelectric properties. Here we show that an effective "interlayer phonon drag" determines the Seebeck coefficient (S) across the van der Waals gap formed in twisted bilayer graphene (tBLG). The cross-plane thermovoltage, which is non-monotonic in both temperature and density, is generated through scattering of electrons by the out-of-plane layer breathing (ZO'/ZA2) phonon modes and differs dramatically from the expected Landauer-Buttiker formalism in conventional tunnel junctions. The tunability of the cross-plane Seebeck effect in van der Waals junctions may be valuable in creating a new genre of versatile thermoelectric systems with layered solids.

This document is the unedited Author's version of a submitted work that was subsequently accepted for publication in Nano Letters, copyright American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/articlesonrequest/AOR-C2EphThhD7U5a4zVMHye

References in corpus (11)

• Thermal properties of graphene: Fundamentals and applications
• Thermoelectric and Magnetothermoelectric Transport Measurements of Graphene
• Single Layer Behavior and Its Breakdown in Twisted Graphene Layers
• The thermopower and Nernst Effect in graphene in a magnetic field
• On the thermoelectricity of correlated electrons in the zero-temperature limit
• Observation of interlayer phonon modes in van der Waals heterostructures
• High Thermoelectric Power Factor in Graphene/hBN Devices
• Raman-scattering study of the phonon dispersion in twisted bi-layer graphene
• Current crowding mediated large contact noise in graphene field-effect transistors
• Cross-plane enhanced thermoelectricity and phonon suppression in graphene/MoS2 van der Waals heterostructures
• Enhanced thermoelectric figure of merit in vertical graphene junctions

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