Odd and even modes of neutron spin resonance in the bilayer iron-based superconductor CaKFe${}_4$As${}_4$

Tao Xie, Yuan Wei, Dongliang Gong +7

We report an inelastic neutron scattering study on the spin resonance in the bilayer iron-based superconductor CaKFe${}_4$As${}_4$. In contrast to its quasi-two-dimensional electron st…