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arXiv · 1907.08133

Role of interactions in the energy of the spin resonance peak in Fe-based superconductors

Yu. N. Togushova·M. M. Korshunov
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Abstract

We consider the spin response within the five-orbital model for iron-based superconductors and study two cases: equal and unequal gaps in different bands. In the first case, the spin resonance peak in the superconducting state appears below the characteristic energy scale determined by the gap magnitude, $2Δ_L$. In the second case, the energy scale corresponds to the sum of smaller and larger gap magnitudes, $Δ_L + Δ_S$. Increasing the values of the Hubbard interaction and the Hund's exchange, we observe a shift of the spin resonance energy to lower frequencies.

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Yu. N. Togushova, M. M. Korshunov. 2019-07-17. Role of interactions in the energy of the spin resonance peak in Fe-based superconductors. https://doi.org/10.4028/www.scientific.net%2Fssp.289.212

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