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Updated: Oct 24, 2026

Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Berry curvature and valley topology modulation with electric field in twisted Graphene/hBN moiré heterostructures
Renu Sangwan1, Konstantin Petrovich Katin2, Rakesh Kumar3
1Department of Physics, Indian Institute of Technology Ropar, SAB Building, IIT Ropar, Rupnagar, 140001, India.
Abstract:
The external fields and strain-based phenomena in different interfacial structures (homo/hetero) are the forefront of the current research in moire structures for their exotic quantum phenomena. Here, we report the modulation of valley-based topological phases in graphene/hBN moir´e hetero-structures with electrostatic gating. The Berry curvature and valley-resolved topological invariants vary systematically with the applied electric field (up to 1.0 eV/nm) for the twist angles (θ < 2◦), arising from the electronic reconstructions while preserving the time reversal symmetry. However, the twist angle governs the valley band topology leading to the valley based topological phase transition in the moir´e heterostructure. The tuning of valley topological phases with electric field and twist angles carries potential in valleytronics and nanoelectronics.
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