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arXiv · 1907.06211

Nature of carrier doping in T'-La1.8-xEu0.2SrxCuO4 studied by X-Ray Photoemission and Absorption Spectroscopy

Chun Lin·Masafumi Horio·Takayuki Kawamata·Shin Saito·Keisuke Koshiishi·Shoya Sakamoto·Yujun Zhang·Kohei Yamamoto·Keisuke Ikeda·Yasuyuki Hirata·Kou Takubo·Hiroki Wadati·Akira Yasui·Yasumasa Takagi·Eiji Ikenaga·Tadashi Adachi·Yoji Koike·Atsushi Fujimori
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Abstract

Recently, hole-doped superconducting cuprates with the T'-structure La1.8-xEu0.2SrxCuO4 (LESCO) have attracted a lot of attention. We have performed x-ray photoemission and absorption spectroscopy measurements on as-grown and reduced T0-LESCO. Results show that electrons and holes were doped by reduction annealing and Sr substitution, respectively. However, it is shown that the system remains on the electron-doped side of the Mott insulator or that the charge-transfer gap is collapsed in the parent compound.

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Chun Lin, Masafumi Horio, Takayuki Kawamata, Shin Saito, Keisuke Koshiishi, Shoya Sakamoto, Yujun Zhang, Kohei Yamamoto, Keisuke Ikeda, Yasuyuki Hirata, Kou Takubo, Hiroki Wadati, Akira Yasui, Yasumasa Takagi, Eiji Ikenaga, Tadashi Adachi, Yoji Koike, Atsushi Fujimori. 2019-07-14. Nature of carrier doping in T'-La1.8-xEu0.2SrxCuO4 studied by X-Ray Photoemission and Absorption Spectroscopy. https://doi.org/10.7566/jpsj.88.115004

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