Angle-resolved photoemission spectroscopy of the low-energy electronic structure of superconducting Pr$_2$CuO$_4$ driven by oxygen non-stoichiometry

M. Horio; Y. Krockenberger; K. Koshiishi; S. Nakata; K. Hagiwara; M. Kobayashi; K. Horiba; H. Kumigashira; H. Irie; H. Yamamoto; A. Fujimori

doi:10.1103/physrevb.98.020505

arXiv · 1801.03702

Angle-resolved photoemission spectroscopy of the low-energy electronic structure of superconducting Pr$_2$CuO$_4$ driven by oxygen non-stoichiometry

M. Horio·Y. Krockenberger·K. Koshiishi·S. Nakata·K. Hagiwara·M. Kobayashi·K. Horiba·H. Kumigashira·H. Irie·H. Yamamoto·A. Fujimori

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Abstract

Bulk crystals of electron-doped cuprates with the T'-type structure require both Ce substitutions and reduction annealing for the emergence of superconductivity while the reduction annealing alone can induce superconductivity in thin films of the T'-type cuprates. In order to reveal low-energy electronic states which are responsible for the superconductivity, we have conducted angle-resolved photoemission spectroscopy measurements on thin films of the superconducting Ce-free T'-type cuprate Pr$_2$CuO$_4$. The results indicate that the overall band structure and the Fermi surface area of the superconducting Pr$_2$CuO$_4$ are similar to those of superconducting Ce-doped bulk single crystals, highlighting the importance of the actual electron concentration rather than the Ce concentration when discussing the physical properties of the T'-type cuprates.

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M. Horio, Y. Krockenberger, K. Koshiishi, S. Nakata, K. Hagiwara, M. Kobayashi, K. Horiba, H. Kumigashira, H. Irie, H. Yamamoto, A. Fujimori. 2018-07-17. Angle-resolved photoemission spectroscopy of the low-energy electronic structure of superconducting Pr$_2$CuO$_4$ driven by oxygen non-stoichiometry. https://doi.org/10.1103/physrevb.98.020505

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