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arXiv · 1410.3202

Probing Strongly Correlated 4f-Orbital Symmetry of the Ground State in Yb Compounds by Linear Dichroism in Core-Level Photoemission

Takeo Mori·Satoshi Kitayama·Yuina Kanai·Sho Naimen·Hidenori Fujiwara·Atsushi Higashiya·Kenji Tamasaku·Arata Tanaka·Kensei Terashima·Shin Imada·Akira Yasui·Yuji Saitoh·Kohei Yamagami·Kohei Yano·Taiki Matsumoto·Takayuki Kiss·Makina Yabashi·Tetsuya Ishikawa·Shigemasa Suga·Yoshichika Onuki·Takao Ebihara·Akira Sekiyama
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Abstract

We show that the strongly correlated 4f-orbital symmetry of the ground state is revealed by linear dichroism in core-level photoemission spectra as we have discovered for YbRh2Si2 and YbCu2Si2. Theoretical analysis tells us that the linear dichroism reflects the anisotropic charge distributions resulting from crystalline electric field. We have successfully determined the ground-state 4f symmetry for both compounds from the polarization-dependent angle-resolved core-level spectra at a low temperature well below the first excitation energy. The excited-state symmetry is also probed by temperature dependence of the linear dichroism where the high measuring temperatures are of the order of the crystal-field-splitting energies.

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Takeo Mori, Satoshi Kitayama, Yuina Kanai, Sho Naimen, Hidenori Fujiwara, Atsushi Higashiya, Kenji Tamasaku, Arata Tanaka, Kensei Terashima, Shin Imada, Akira Yasui, Yuji Saitoh, Kohei Yamagami, Kohei Yano, Taiki Matsumoto, Takayuki Kiss, Makina Yabashi, Tetsuya Ishikawa, Shigemasa Suga, Yoshichika Onuki, Takao Ebihara, Akira Sekiyama. 2014-10-13. Probing Strongly Correlated 4f-Orbital Symmetry of the Ground State in Yb Compounds by Linear Dichroism in Core-Level Photoemission. https://doi.org/10.7566/jpsj.83.123702

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