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Published on: June 28, 2018
Material Realization of Spinless, Covalent-Type Dirac Semimetals in Three Dimensions
Yuki Tanaka1, Rinsuke Yamada1, Manabu Sato1
1The University of Tokyo, Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Bunkyo, Tokyo 113-8656, Japan.
Abstract:
Realization of a three-dimensional (3D) analog of graphene has been a central challenge in topological materials science. Graphene is stabilized by covalent bonding, unlike conventional spin-orbit-type 3D Dirac semimetals (DSMs). In this study, we demonstrate the material realization of covalent-type 3D DSMs R_{8}CoX_{3} stabilized by covalent bonding. We confirm the clean Dirac semimetal state in Y_{8}CoIn_{3} by combined thermodynamic and transport experiments. We also realize high carrier mobility exceeding 3000 cm^{2}/Vs even in polycrystalline samples of R_{8}CoX_{3}. Our research provides a material platform for exploration of Dirac electrons in three dimensions with wide chemical tunability.
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