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arXiv · 1606.01174

Semimetallic "Electride Bands" Derived from Interlayer Electrons in Quasi-Two-Dimensional Electride Y$_2$C

Koji Horiba·Ryu Yukawa·Taichi Mitsuhashi·Miho Kitamura·Takeshi Inoshita·Noriaki Hamada·Shigeki Otani·Naoki Ohashi·Sachiko Maki·Jun-ichi Yamaura·Hideo Hosono·Youichi Murakami·Hiroshi Kumigashira
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Abstract

Two-dimensional (2D) electrides are a new concept material in which anionic electrons are confined in the interlayer space between positively charged layers. We have performed angle-resolved photoemission spectroscopy measurements on Y$_2$C, which is a possible 2D electride, in order to verify the formation of 2D electride states in Y$_2$C. We clearly observe the existence of semimetallic "electride bands" near the Fermi level, as predicted by ${ab}$ ${initio}$ calculations, conclusively demonstrating that Y$_2$C is a quasi-2D electride with electride bands derived from interlayer anionic electrons.

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Koji Horiba, Ryu Yukawa, Taichi Mitsuhashi, Miho Kitamura, Takeshi Inoshita, Noriaki Hamada, Shigeki Otani, Naoki Ohashi, Sachiko Maki, Jun-ichi Yamaura, Hideo Hosono, Youichi Murakami, Hiroshi Kumigashira. 2016-06-03. Semimetallic "Electride Bands" Derived from Interlayer Electrons in Quasi-Two-Dimensional Electride Y$_2$C. https://doi.org/10.1103/physrevb.96.045101

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