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arXiv · 2005.00262

Emergence of Nearly Flat Bands through an Embedded Kagome Lattice in an Epitaxial Two-dimensional Ge Layer on ZrB2(0001)

Antoine Fleurence·Chi-Cheng Lee·Rainer Friedlein·Yuki Fukaya·Shinya Yoshimoto·Kozo Mukai·Hiroyuki Yamane·Nobuhiro Kosugi·Jun Yoshinobu·Taisuke Ozaki·Yukiko Yamada-Takamura
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Abstract

Ge atoms segregating on zirconium diboride thin films grown on Ge(111) were found to crystallize into a two-dimensional bitriangular structure which was recently predicted to be a flat band material. Angle-resolved photoemission experiments together with theoretical calculations verified the existence of a nearly flat band in spite of non-negligible in-plane long-range hopping and interactions with the substrate. This provides the first experimental evidence that a flat band can emerge from the electronic coupling between atoms and not from the geometry of the atomic structure.

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Antoine Fleurence, Chi-Cheng Lee, Rainer Friedlein, Yuki Fukaya, Shinya Yoshimoto, Kozo Mukai, Hiroyuki Yamane, Nobuhiro Kosugi, Jun Yoshinobu, Taisuke Ozaki, Yukiko Yamada-Takamura. 2020-05-01. Emergence of Nearly Flat Bands through an Embedded Kagome Lattice in an Epitaxial Two-dimensional Ge Layer on ZrB2(0001). https://doi.org/10.1103/physrevb.102.201102

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