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Emulating Heavy Fermions in Twisted Trilayer Graphene
1Condensed Matter Theory Group, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland.
Physical Review Letters
|July 23, 2021
Summary
Twisted trilayer graphene emulates heavy fermion physics, enabling electrical control over magnetic and heavy fermion states. This carbon-based platform offers a new way to study strongly correlated phenomena.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Twisted van der Waals materials exhibit tunable electronic structures.
- Heavy fermion physics involves strongly correlated electron behavior.
Purpose of the Study:
- To establish twisted trilayer graphene (TTG) as a platform for emulating heavy fermion physics.
- To investigate the tunability of electronic structures and emergent phenomena in TTG.
Main Methods:
- Theoretical modeling and simulation of twisted trilayer graphene.
- Analysis of electronic structures, including extended and localized modes.
- Investigation of electron-electron interactions and their effects.
Main Results:
- TTG hosts tunable electronic structures with controllable extended and localized modes via interlayer bias.
- Localized modes develop local moments that undergo Kondo coupling with extended states.
- Electrical control allows tuning between magnetic and heavy fermion regimes, exploring a generalized Doniach phase diagram.
Conclusions:
- Twisted trilayer graphene serves as a novel, purely carbon-based platform for realizing and studying strongly correlated heavy fermion physics.
- The ability to electrically control the system offers new avenues for exploring quantum critical phenomena.
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