Related Experiment Videos
Energy-Dependent Chirality Effects in Quasifree-Standing Graphene
Daniela Dombrowski1,2, Wouter Jolie2, Marin Petrović3
1Institut für Materialphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
Physical Review Letters
|April 4, 2017
Summary
Chirality in graphene is experimentally shown to be broken due to electron scattering. This study identifies a new scattering channel and highlights higher-order hopping effects impacting graphene
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Graphene exhibits unique electronic properties due to its chiral nature.
- Understanding electron scattering is crucial for graphene-based electronics.
Purpose of the Study:
- To provide direct experimental evidence of broken chirality in graphene.
- To investigate electron scattering processes and their relation to graphene's electronic structure.
- To identify new scattering mechanisms and their impact on chirality.
Main Methods:
- Analysis of electron scattering processes across a range of energies.
- Measurement of the van Hove singularity energy at the M point.
- Comparison of experimental data with theoretical calculations and T-matrix simulations.
- Investigation with and without a pseudomagnetic field.
Main Results:
- Direct experimental evidence for broken chirality in graphene was obtained.
- The energy of the van Hove singularity at the M point was measured.
- A novel intravalley scattering channel, not suppressed by chirality, was identified.
- Experimental data showed strong agreement with theoretical models for free-standing graphene.
Conclusions:
- Higher-order electron hopping effects are key to breaking chirality near the van Hove singularity.
- The findings offer insights into the fundamental electronic behavior of graphene.
- This work contributes to the understanding of electron dynamics in low-dimensional materials.