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arXiv · 1504.06248

Evidence for Gamma_8 Ground-State Symmetry of Cubic YbB12 Probed by Linear Dichroism in Core-Level Photoemission

Yuina Kanai·Takeo Mori·Sho Naimen·Kohei Yamagami·Hidenori Fujiwara·Atsushi Higashiya·Toshiharu Kadono·Shin Imada·Takayuki Kiss·Arata Tanaka·Kenji Tamasaku·Makina Yabashi·Tetsuya Ishikawa·Fumitoshi Iga·Akira Sekiyama
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Abstract

We have successfully observed linear dichroism in angle-resolved Yb3+ 3d5/2 core-level photoemission spectra for YbB12 in cubic symmetry. Its anisotropic 4f charge distribution due to the crystal-field splitting is responsible for the linear dichroism, which has been verified by spectral simulations using ionic calculations with the full multiplet theory for a single-site Yb3+ ion in cubic symmetry. The observed linear dichroism as well as the polarization-dependent spectra in two different photoelectron directions for YbB12 are quantitatively reproduced by theoretical analysis for the Gamma_8 ground state, indicating the Gamma_8 ground-state symmetry for the Yb3+ ions mixed with the Yb2+ state.

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Yuina Kanai, Takeo Mori, Sho Naimen, Kohei Yamagami, Hidenori Fujiwara, Atsushi Higashiya, Toshiharu Kadono, Shin Imada, Takayuki Kiss, Arata Tanaka, Kenji Tamasaku, Makina Yabashi, Tetsuya Ishikawa, Fumitoshi Iga, Akira Sekiyama. 2015-04-23. Evidence for Gamma_8 Ground-State Symmetry of Cubic YbB12 Probed by Linear Dichroism in Core-Level Photoemission. https://doi.org/10.7566/jpsj.84.073705

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