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Updated: Aug 11, 2026
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Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Heavy-Fermion Phase Diagram in Magic-Angle Twisted Trilayer Graphene
Le Zhang1,2, Wenqiang Zhou1, Xinjie Fang1
1Westlake University, Key Laboratory for Quantum Materials of Zhejiang Province, Department of Physics, School of Science, Hangzhou, China.
Physical Review Letters
|August 10, 2026
Summary
We demonstrate an electrically tunable heavy fermion phase diagram in magic-angle twisted trilayer graphene. This platform allows control over quantum phase transitions and offers new avenues for exploring exotic quantum states.
Area of Science:
- Condensed matter physics
- Quantum materials
- Two-dimensional heterostructures
Background:
- Localized magnetic moments and itinerant electrons drive exotic quantum states.
- Moiré heterostructures offer tunable electronic properties.
Purpose of the Study:
- To demonstrate an electrically tunable heavy fermion phase diagram in magic-angle twisted trilayer graphene.
- To explore quantum phase transitions and correlated quantum phases in 2D systems.
Main Methods:
- Utilizing a displacement field to control Kondo hybridization.
- Investigating the interplay between localized flat-band electrons and itinerant Dirac electrons.
Main Results:
- Observed a continuous quantum phase transition from antiferromagnetic semimetal to paramagnetic heavy fermion metal.
- Detected effective mass divergence and Fermi surface reconstruction at the quantum critical point.
Conclusions:
- Magic-angle twisted trilayer graphene provides a tunable platform for heavy fermion physics.
- Moiré heterostructures are versatile for exploring 2D correlated quantum phases, including unconventional superconductivity.
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