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arXiv · 0710.3615

Paramagnonlike excitations and spin diffusion in magnetic resonance studies of copper oxide superconductors

Igor A. Larionov
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Abstract

The relaxation function theory for a doped two-dimensional Heisenberg antiferromagnetic system in the paramagnetic state for all wave vectors through the Brillouin zone is presented in view of low frequency response of high-$T_c$ copper oxide superconductors. We deduced the regions of long lifetime [$T \lesssim 400(1-4x)$ K] and "overdamped" [$T \gtrsim 700(1-4x)$ K] paramagnonlike excitations in the temperature ($T$)-doping index ($x$) phase diagram from plane oxygen nuclear spin-lattice relaxation rate $^{17}(1/T_1)$ data in up to optimally doped La$_{2-x}$Sr$_{x}$CuO$_{4}$ thus providing the regimes for the spin wave concept and the ''overdamped'' mode.

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Igor A. Larionov. 2007-10-19. Paramagnonlike excitations and spin diffusion in magnetic resonance studies of copper oxide superconductors. https://doi.org/10.1103/physrevb.76.224503

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