Related Experiment Video
Updated: May 30, 2025
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
9.4K
Quasiperiodic Pairing in Graphene Quasicrystals
Rasoul Ghadimi1,2,3, Bohm-Jung Yang1,2,3
1Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea.
Nano Letters
|January 27, 2025
Summary
Superconductivity in twisted bilayer graphene quasicrystals differs between periodic and quasiperiodic energy ranges. Quasiperiodic ranges exhibit enhanced, nonuniform superconductivity due to local density of states variations.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Twisted bilayer graphene quasicrystals (TBGQCs) exhibit unique electronic properties due to their quasiperiodic structure.
- Understanding superconductivity in these novel materials is crucial for next-generation electronic applications.
Purpose of the Study:
- To investigate the nature of superconducting instabilities in TBGQCs.
- To differentiate superconductivity mechanisms in periodic energy ranges (PERs) and quasiperiodic energy ranges (QERs).
Main Methods:
- Analysis of the electronic energy spectrum of TBGQCs.
- Examination of the local density of states (LDOS) distribution.
- Theoretical investigation of superconducting pairing instabilities.
Main Results:
- Superconductivity in PERs is a superposition of monolayer superconductivity due to weak interlayer coupling.
- Superconductivity in QERs is enhanced and exhibits nonuniform pairing amplitudes.
- Quasiperiodic superconductivity arises from inhomogeneous LDOS distribution in QERs.
Conclusions:
- The study provides a theoretical framework to explain observed superconductivity in moiré quasicrystals.
- Distinct superconducting behaviors in PERs and QERs are elucidated.
- Inhomogeneous electronic states in QERs are key to understanding quasiperiodic superconductivity.
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