Thermal biasing for lattice symmetry breaking and topological edge state imaging

Bibliographic Details
Title: Thermal biasing for lattice symmetry breaking and topological edge state imaging
Authors: Dohyun Kim, Jaeuk Seo, Sangsu Yer, Seungil Baek, Woohyun Cho, Shoujun Zheng, Yong-Hyun Kim, Mali Zhao, Heejun Yang
Source: Nature Communications, Vol 16, Iss 1, Pp 1-8 (2025)
Publisher Information: Nature Portfolio, 2025.
Publication Year: 2025
Collection: LCC:Science
Subject Terms: Science
More Details: Abstract Marginally twisted bilayer graphene with large Bernal stacked domains involves symmetry-breaking features with domain boundaries that exhibit topological edge states normally obscured by trivial bands. A vertical electric field can activate these edge states through inversion symmetry breaking and opening a bandgap around the edge state energy. However, harnessing pristine topological states at the Fermi level without violent electric or magnetic bias remains challenging, particularly above room temperature. Here, we demonstrate that thermal biasing can break the vertically stacked lattice symmetry of twisted bilayer graphene via the interatomic Seebeck effect, enabling thermoelectric imaging of topological edge states at tunable Fermi levels above room temperature. The high spatial resolution in the imaging is achieved through atomic-scale thermopower generation between a metallic tip and the sample, reflecting the local electronic band structure and its derivative features of twisted bilayer graphene at the Fermi level. Our findings suggest that thermal biasing provides a sensitive, non-destructive method for symmetry breaking and topological state imaging above room temperature, making it a practical and accessible approach.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2041-1723
Relation: https://doaj.org/toc/2041-1723
DOI: 10.1038/s41467-025-57194-x
Access URL: https://doaj.org/article/fc83bf7d1f3a407fa01bb84406160983
Accession Number: edsdoj.fc83bf7d1f3a407fa01bb84406160983
Database: Directory of Open Access Journals
More Details
ISSN:20411723
DOI:10.1038/s41467-025-57194-x
Published in:Nature Communications
Language:English