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arXiv · 0909.5567

Spin-roton excitations in the cuprate superconductors

J. W. Mei·Z. Y. Weng
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Abstract

We identify a new kind of elementary excitations, spin-rotons, in the doped Mott insulator. They play a central role in deciding the superconducting transition temperature Tc, resulting in a simple Tc formula,Tc=Eg/6, with Eg as the characteristic energy scale of the spin rotons. We show that the degenerate S=1 and S=0 rotons can be probed by neutron scattering and Raman scattering measurements, respectively, in good agreement with the magnetic resonancelike mode and the Raman A1g mode observed in the high-Tc cuprates.

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J. W. Mei, Z. Y. Weng. 2009-09-30. Spin-roton excitations in the cuprate superconductors. https://doi.org/10.1103/physrevb.81.014507

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