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Spin Dynamics near the Superconductor-to-Insulator Transition in Impurity-Doped YBa2Cu4O8

Y. Itoh·T. Machi·N. Watanabe·S. Adachi·N. Koshizuka
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Abstract

We studied low-frequency spin dynamics near the impurity-induced superconductor-to-insulator transition for underdoped high-Tc superconductor YBa2(Cu1-xMx)4O8 (M=Ni, Zn) using the Cu nuclear quadrupole resonance (NQR) spin-echo technique. We observed remarkable suppression of the normal-state pseudo spin-gap and a loss of Cu NQR spectrum intensity at low temperatures around the critical impurity concentration.

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Y. Itoh, T. Machi, N. Watanabe, S. Adachi, N. Koshizuka. 2001-07-10. Spin Dynamics near the Superconductor-to-Insulator Transition in Impurity-Doped YBa2Cu4O8. https://doi.org/10.1143/jpsj.70.1881

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