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arXiv · 2107.04350

Semimetallic Nature and Magnetic Polarons in EuB6 Studied by Angle-Resolved Photoemission Spectroscopy

Chul-Hee Min·Boyoun Kang·Beong Ki Cho·En-Jin Cho·Byeong-Gyu Park·Hyeong-Do Kim
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Abstract

Temperature-dependent angle-resolved photoemission spectroscopy (ARPES) was carried out on single-crystalline EuB6 samples. By measuring ARPES spectra in an extended Brillouin zone, a B 2p hole pocket centered at the X point is clearly observed, thus proving the semimetallic nature of EuB6. Below the Curie temperature TC, ARPES spectra show two B 2p bands of which separation is due to an exchange interaction between local Eu 4f and itinerant B 2p electrons. The exchange splitting becomes smaller as the temperature increases and disappears well above TC. Additionally, a diffuse structure near the Fermi level survives just above TC. Such behavior is well described by Monte Carlo simulations of a Kondo lattice model, thus supporting the formation of magnetic polarons in EuB6, which accounts for the resistivity upturn near above TC when lowering the temperature.

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Chul-Hee Min, Boyoun Kang, Beong Ki Cho, En-Jin Cho, Byeong-Gyu Park, Hyeong-Do Kim. 2021-07-09. Semimetallic Nature and Magnetic Polarons in EuB6 Studied by Angle-Resolved Photoemission Spectroscopy. https://doi.org/10.1007/s40042-021-00273-1

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