Temperature Dependence of the Cu(2) NQR Line Width in YBa$_2$Cu$_3$O$_{7-y}$

A. V. Dooglav; M. V. Eremin; Yu. A. Sakhratov; A. V. Savinkov

doi:10.1134/1.1405895

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Temperature Dependence of the Cu(2) NQR Line Width in YBa$_2$Cu$_3$O$_{7-y}$

A. V. Dooglav·M. V. Eremin·Yu. A. Sakhratov·A. V. Savinkov

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Abstract

Systematic measurements of the $^{63}$Cu(2) NQR line width were performed in underdoped YBa$_2$Cu$_3$O$_{7-y}$ samples over the temperature range 4.2 K $<T<300$ K. It was shown that the copper NQR line width monotonically increases upon lowering temperature in the below-critical region, resembling temperature behavior of the superconducting gap. The observed dependence is explained by the fact that the energy of a condensate of sliding charge-current states of the charge-density-wave type depends on the phase of order parameter. Calculations show that this dependence appears only at $T<T_c$. Quantitative estimates of the line broadening at $T<T_c$ agree with the measurement results.

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A. V. Dooglav, M. V. Eremin, Yu. A. Sakhratov, A. V. Savinkov. 2001-08-14. Temperature Dependence of the Cu(2) NQR Line Width in YBa$_2$Cu$_3$O$_{7-y}$. https://doi.org/10.1134/1.1405895

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