Reduction annealing effects on the crystal structure of $T^{\prime}$-type La$_{1.8}$Eu$_{0.2}$CuO$_{4+\alpha-\delta}$

Masaki Fujita; Takanori Taniguchi; Shuki Torii; Takashi Kamiyama; Koki Ohashi; Takayuki Kawamata; Tomohisa Takamatsu; Tadashi Adachi; Masatsune Kato; Yoji Koike

doi:10.7566/jpsj.90.105002

arXiv · 2108.02078

Reduction annealing effects on the crystal structure of $T^{\prime}$-type La$_{1.8}$Eu$_{0.2}$CuO$_{4+\alpha-\delta}$

Masaki Fujita·Takanori Taniguchi·Shuki Torii·Takashi Kamiyama·Koki Ohashi·Takayuki Kawamata·Tomohisa Takamatsu·Tadashi Adachi·Masatsune Kato·Yoji Koike

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Abstract

We performed neutron powder diffraction measurements on the as-sintered (AS) and oxygen-reduced (OR) La$_{1.8}$Eu$_{0.2}$CuO$_{4+\alpha-\delta}$ (LECO). The structural parameters for oxygens in AS and OR samples refined by the Rietveld analysis are almost identical to those of the reference system, Pr$_{2}$CuO$_{4+\alpha-\delta}$. Thus, the two systems are comparable in terms of the structural changes in oxygens due to the annealing, although superconductivity appears only in LECO.

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Masaki Fujita, Takanori Taniguchi, Shuki Torii, Takashi Kamiyama, Koki Ohashi, Takayuki Kawamata, Tomohisa Takamatsu, Tadashi Adachi, Masatsune Kato, Yoji Koike. 2021-08-04. Reduction annealing effects on the crystal structure of $T^{\prime}$-type La$_{1.8}$Eu$_{0.2}$CuO$_{4+\alpha-\delta}$. https://doi.org/10.7566/jpsj.90.105002

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