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Updated: Dec 25, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Experimental evidence of a new class of massless fermions
Marek Kopciuszyński1, Mariusz Krawiec, Lucyna Żurawek
1Institute of Physics, Maria Curie-Sklodowska University, 20-031 Lublin, Poland. ryszard.zdyb@umcs.pl.
Abstract:
The discovery of graphene with its massless fermions established a new branch of nanomaterials in which linear bands can be realized. It has been predicted that beside Dirac fermions revealing isotropic character and observed in a number of two-dimensional materials, another class of massless fermions can also be found: strongly anisotropic fortune teller-like states which form planes instead of cones in the electronic structure. Here, we demonstrate that such distinct electronic structures exist and can be found in a surface layer of silicon.
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