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arXiv · 0902.1381

Superexchange Interaction and Magnetic Moment in Antiferromagnetic High-T_c Copper-oxide Superconductors

Yoshio Kitaoka·Hidekazu Mukuda·Sunao Shimizu
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Abstract

Extensive Cu-NMR studies on multilayered high-Tc cuprates have deduced the following results;(1) Antiferromagnetic (AFM) moment M_{AFM} is decreased with doping, regardless of the number of CuO_2 layers n, and collapses around a carrier density N_h = 0.17. (2) The AFM ordering temperature is enhanced as the out-of-plane coupling J_{out} increases with increasing n. (3) The in-plane superexchange J_{in} is invariant with doping, but is even increased. (4) The dome shape of T_c from the underdoped to the overdoped regime with a maximum T_c at N_h = 0.22 does not depend on n, but its maximum value of T_c seems to depend on n moderately. The present results strongly suggest that the AFM interaction plays the vital role as the glue for the Cooper pairs, which will lead us to a genuine understanding of why the T_c of cuprate superconductors is so high.

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Yoshio Kitaoka, Hidekazu Mukuda, Sunao Shimizu. 2009-02-09. Superexchange Interaction and Magnetic Moment in Antiferromagnetic High-T_c Copper-oxide Superconductors. https://arxiv.org/abs/0902.1381

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