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arXiv · 2103.16072

Electronic structure of URu$_2$Si$_2$ in paramagnetic phase: Three-dimensional angle resolved photoelectron spectroscopy study

Shin-ichi Fujimori·Yukiharu Takeda·Hiroshi Yamagami·Etsuji Yamamoto·Yoshinori Haga
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Abstract

The three-dimensional (3D) electronic structure of the hidden order compound URu$_2$Si$_2$ in a paramagnetic phase was revealed using a 3D angle-resolved photoelectron spectroscopy where the electronic structure of the entire Brillouin zone is obtained by scanning both incident photon energy and detection angles of photoelectrons. The quasi-particle bands with enhanced contribution from the $\mathrm{U}~5f$ state were observed near $E_\mathrm{F}$, formed by the hybridization with the $\mathrm{Ru}~4d$ states. The energy dispersion of the quasi-particle band is significantly depend on $k_z$, indicating that they inherently have a 3D nature. The band-structure calculation qualitatively explain the characteristic features of the band structure and Fermi surface although the electron correlation effect strongly renormalizes the quasi-particle bands. The 3D and strongly-correlated nature of the quasi-particle bands in URu$_2$Si$_2$ is an essential ingredient for modeling its hidden-order transition.

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Shin-ichi Fujimori, Yukiharu Takeda, Hiroshi Yamagami, Etsuji Yamamoto, Yoshinori Haga. 2021-03-30. Electronic structure of URu$_2$Si$_2$ in paramagnetic phase: Three-dimensional angle resolved photoelectron spectroscopy study. https://arxiv.org/abs/2103.16072

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