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تسجيل مستخدم جديدOxygen isotope effect on superconductivity and magnetism in Y_1-xPr_xBa_2Cu_3O_7-delta
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Oxygen isotope (^{16}O/^{18}O) effects (OIEs) on the superconducting transition (T_c), the spin-glass ordering (T_g), and the antiferromagnetic ordering (T_N) temperatures were studied for Y_1-xPr_xBa_2Cu_3O_7-delta as a function of Pr content (0.0leq x leq 1.0). The OIE on T_c increases with increasing x up to xapprox0.55, where superconductivity disappears. For decreasing x the OIEs on T_N and T_g increase down to xapprox 0.7 where antiferromagnetic order and down to xapprox0.3 where spin-glass behavior vanish, respectively. The OIEs on T_g and T_N are found to have {it opposite signs} as compared to the OIE on T_c. All OIEs are suggested to arise from the isotope dependent mobility (kinetic energy) of the charge carriers.
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Muon-spin rotation (muSR) studies of the oxygen isotope (^{16}O/^{18}O) effect (OIE) on the in-plane magnetic field penetration depth lambda_{ab} in cuprate high-temperature superconductors (HTS) are presented. First, the doping dependence of the OIE
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Oxygen-isotope effect has been investigated in a recently discovered superconductor Sr_{0.4}K_{0.6}BiO_{3}. This compound has a distorted perovskite structure and becomes superconducting at about 12 K. Upon replacing ^{16}O with ^{18}O by 60-80%, the
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We report the first direct observation of the oxygen-isotope ($^{16}$O/$^{18}$O) effect on the in-plane penetration depth $lambda_{ab}$ in a nearly optimally doped YBa$_2$Cu$_3$O$_{7-delta}$ film using the novel low-energy muon-spin rotation techniqu
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ope exponent $alpha$ monotonously increases without any anomaly around $p = 1/8$. The monotonous increase in $alpha$ indicates that phonons are involved in the mechanism which causes the monotonous $T_c$ suppression with underdoping.
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