Magnetic Vortices in High Temperature Superconductors

Per Hedegard

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arXiv · cond-mat/0102070

Magnetic Vortices in High Temperature Superconductors

Per Hedegard

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Abstract

It is suggested that modes, observed in recent neutron scattering experiments by Lake {\it et al.}, on La$_{2-x}$Sr$_x$CuO$_4$ in strong magnetic fields ($\approx$ 7 T), are due to the existence of antiferromagnetic moments associated with the cores of vortices generated by the field. These moments form one-dimensional chains along the $c$-axis (the vortex axis), which at finite temperatures are disordered. At temperatures higher than 10 K the correlation length gets shorter than the lattice parameter, resulting in no scattering from coherent spin-waves above that temperature. The bandwidth of the spin-waves is estimated to be $\approx$ 4 meV in accordance with the observations.

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Per Hedegard. 2001-02-06. Magnetic Vortices in High Temperature Superconductors. https://arxiv.org/abs/cond-mat/0102070

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