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arXiv · 1702.00592

Dirac fermions in borophene

Baojie Feng·Osamu Sugino·Ro-Ya Liu·Jin Zhang·Ryu Yukawa·Mitsuaki Kawamura·Takushi Iimori·Howon Kim·Yukio Hasegawa·Hui Li·Lan Chen·Kehui Wu·Hiroshi Kumigashira·Fumio Komori·Tai-Chang Chiang·Sheng Meng·Iwao Matsuda
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Abstract

Honeycomb structures of group IV elements can host massless Dirac fermions with non-trivial Berry phases. Their potential for electronic applications has attracted great interest and spurred a broad search for new Dirac materials especially in monolayer structures. We present a detailed investigation of the \beta 12 boron sheet, which is a borophene structure that can form spontaneously on a Ag(111) surface. Our tight-binding analysis revealed that the lattice of the \beta 12-sheet could be decomposed into two triangular sublattices in a way similar to that for a honeycomb lattice, thereby hosting Dirac cones. Furthermore, each Dirac cone could be split by introducing periodic perturbations representing overlayer-substrate interactions. These unusual electronic structures were confirmed by angle-resolved photoemission spectroscopy and validated by first-principles calculations. Our results suggest monolayer boron as a new platform for realizing novel high-speed low-dissipation devices.

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Baojie Feng, Osamu Sugino, Ro-Ya Liu, Jin Zhang, Ryu Yukawa, Mitsuaki Kawamura, Takushi Iimori, Howon Kim, Yukio Hasegawa, Hui Li, Lan Chen, Kehui Wu, Hiroshi Kumigashira, Fumio Komori, Tai-Chang Chiang, Sheng Meng, Iwao Matsuda. 2017-02-02. Dirac fermions in borophene. https://doi.org/10.1103/physrevlett.118.096401

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