Phase diagram of YBa$_2$Cu$_3$O$_{7-y}$ at T$<$T$_c$ based on Cu(2) transverse nuclear relaxation

M. V. Eremin; Yu. A. Sakhratov; A. V. Savinkov; A. V. Dooglav; I. R. Mukhamedshin; A. V. Egorov

doi:10.1134/1.1387523

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Phase diagram of YBa$_2$Cu$_3$O$_{7-y}$ at T$<$T$_c$ based on Cu(2) transverse nuclear relaxation

M. V. Eremin·Yu. A. Sakhratov·A. V. Savinkov·A. V. Dooglav·I. R. Mukhamedshin·A. V. Egorov

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Abstract

Two maxima in transverse relaxation rate of Cu(2) nuclei in YBa$_2$Cu$_3$O$_{7-y}$ are observed, at T = 35 K and T = 47 K. Comparison of the $^{63}$Cu(2) and $^{65}$Cu(2) rates at T = 47 K indicates the magnetic character of relaxation. The enhancement at T = 47 K of fluctuating local magnetic fields perpendicular to the CuO$_2$ planes is connected with the critical fluctuations of orbital currents. Maximum at T = 35 K is connected with the appearance of inhomogeneous supeconducting phase. Together with data published to date, our experimental results allow to suggest a qualitatively new phase diagram of the superconducting phase.

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M. V. Eremin, Yu. A. Sakhratov, A. V. Savinkov, A. V. Dooglav, I. R. Mukhamedshin, A. V. Egorov. 2001-05-26. Phase diagram of YBa$_2$Cu$_3$O$_{7-y}$ at T$<$T$_c$ based on Cu(2) transverse nuclear relaxation. https://doi.org/10.1134/1.1387523

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