Effect of phase fluctuations on INS and NMR experiments in the pseudo-gap regime of the underdoped cuprates

Harry Westfahl Jr.; Dirk K. Morr

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arXiv · cond-mat/0002039

Effect of phase fluctuations on INS and NMR experiments in the pseudo-gap regime of the underdoped cuprates

Harry Westfahl Jr.·Dirk K. Morr

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Abstract

We present a theory for inelastic neutron scattering (INS) and nuclear magnetic resonance (NMR) experiments in the pseudo-gap regime of the underdoped high-$T_c$ cuprates. We show that superconducting phase fluctuations greatly affect the temperature and frequency dependence of the spin-susceptibility, $χ''$, probed by both experimental techniques. This result explains the appearance of a {\it resonance peak}, observed in INS experiments, below a temperature $T_0 > T_c$. In the same temperature regime, we find that the $^{63}$Cu spin-lattice relaxation rate, $1/T_1$, measured in NMR experiments, is suppressed. Our results are in qualitative agreement with the available experimental data.

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Harry Westfahl Jr., Dirk K. Morr. 2000-02-02. Effect of phase fluctuations on INS and NMR experiments in the pseudo-gap regime of the underdoped cuprates. https://arxiv.org/abs/cond-mat/0002039

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