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Nearly Singular Magnetic Fluctuations in the Normal State of a High-T_c Cuprate Superconductor

G. Aeppli·T. E. Mason·S. M. Hayden·H. A. Mook·J. Kulda
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Abstract

Polarized and unpolarized neutron scattering was used to measure the wave vector- and frequency-dependent magnetic fluctuations in the normal state (from the superconducting transition temperature, T_c=35, up to 350 K) of single crystals of La_{1.86}Sr_{0.14}CuO_4. The peaks which dominate the fluctuations have amplitudes that decrease as T^{-2} and widths that increase in proportion to the thermal energy, k_B T (where k_B is Boltzmann's constant), and energy transfer added in quadrature. The nearly singular fluctuations are consistent with a nearby quantum critical point.

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G. Aeppli, T. E. Mason, S. M. Hayden, H. A. Mook, J. Kulda. 1998-01-16. Nearly Singular Magnetic Fluctuations in the Normal State of a High-T_c Cuprate Superconductor. https://arxiv.org/abs/cond-mat/9801169

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