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تسجيل مستخدم جديدElectron-Doping Effect on Tc in the Undoped (Ce-Free) Superconductor T-La1.8Eu0.2CuO4 Studied by the Fluorine Substitution for Oxygen
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We have succeeded in synthesizing electron-doped polycrystalline bulk samples of T-La1.8Eu0.2CuO4-yFy (y = 0 - 0.15) by the fluorination of undoped (Ce-free) T-La1.8Eu0.2CuO4 using NH4F. The magnetic susceptibility measurements have revealed that the superconducting transition temperature, Tc, increases with increasing y, exhibits the maximum of 23 K at y = 0.025, and decreases. The dome-like dependence of Tc on the doped carrier concentration in the T-type (La,Eu)-based cuprates is explained in terms of the pairing mediated by spin fluctuations based on the d-p model calculation [K. Yamazaki et al., J. Phys.: Conf. Ser. 871, 012009 (2017)].
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In order to investigate the electronic state of Ce-free and Ce-underdoped high-Tc cuprates with the so-called T structure, we have performed muon-spin-relaxation (muSR) and specific-heat measurements of Ce-free T-La_1.8_Eu_0.2_CuO_4+d_ (T-LECO) polyc
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We have investigated the effects of magnetic Ni and nonmagnetic Zn impurities on the superconductivity in undoped T-La$_{1.8}$Eu$_{0.2}$CuO$_4$ (T-LECO) with the Nd$_2$CuO$_4$-type structure, using the polycrystalline bulk samples, to clarify the pai
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