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Theory of incommensurate magnetic correlations across the insulator-superconductor transition in underdoped La_{2-x}Sr_xCuO_4

Oleg P. Sushkov·Valeri N. Kotov
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Abstract

The main feature in the elastic neutron scattering of La_{2-x}Sr_xCuO_4 is the existence of incommensurate peaks with positions that jump from 45 to 0 degrees at 5% doping. We show that the spiral state of the t-t'-t''-J model with realistic parameters describes this data perfectly. We explain why in the insulator the peak is at 45 degrees while it switches to 0 degrees precisely at the insulator-metal transition. The calculated positions of the peaks are in agreement with the data in both phases.

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Oleg P. Sushkov, Valeri N. Kotov. 2004-12-29. Theory of incommensurate magnetic correlations across the insulator-superconductor transition in underdoped La_{2-x}Sr_xCuO_4. https://doi.org/10.1103/physrevlett.94.097005

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