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arXiv · 2108.05832

Polarized neutron scattering studies of magnetic excitations in iron-selenide superconductor (Li$_{0.8}$Fe$_{0.2}$)ODFeSe ($T_c$ = 41 K)

Die Hu·Yu Feng·Jitae T. Park·Hongliang Wo·Qisi Wang·Frederic Bourdarot·Alexandre Ivanov·Jun Zhao
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Abstract

We report polarized neutron scattering measurements of the low energy spin fluctuations of the iron-selenide superconductor Li$_{0.8}$Fe$_{0.2}$ODFeSe below and above its superconducting transition temperature $T_c=41$ K. Our experiments confirmed that the resonance mode near 21 meV is magnetic. Moreover, the spin excitations are essentially isotropic in spin space at 5$\leq E\leq$ 29 meV in the superconducting and normal states. Our results suggest that the resonance mode in iron-based superconductors becomes isotropic when the influence of spin-orbit coupling and magnetic/nematic order is minimized, similar to those observed in cuprate superconductors.

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Die Hu, Yu Feng, Jitae T. Park, Hongliang Wo, Qisi Wang, Frederic Bourdarot, Alexandre Ivanov, Jun Zhao. 2021-08-12. Polarized neutron scattering studies of magnetic excitations in iron-selenide superconductor (Li$_{0.8}$Fe$_{0.2}$)ODFeSe ($T_c$ = 41 K). https://doi.org/10.1088/1361-648x%2Fac1d16

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