Structure of spin excitations in heavily electron-doped Li_0.8Fe_0.2ODFeSe superconductors.

ABSTRACT: Heavily electron-doped iron-selenide high-transition-temperature (high-T _c) superconductors, which have no hole Fermi pockets, but have a notably high T _c, have challenged the prevailing s _± pairing scenario originally proposed for iron pnictides containing both electron and hole pockets. The microscopic mechanism underlying the enhanced superconductivity in heavily electron-doped iron-selenide remains unclear. Here, we used neutron scattering to study the spin excitations of the heavily electron-doped iron-selenide material Li_0.8Fe_0.2ODFeSe (T _c = 41 K). Our data revealed nearly ring-shaped magnetic resonant excitations surrounding (π, π) at ∼21 meV. As the energy increased, the spin excitations assumed a diamond shape, and

SUBMITTER: Pan B 

PROVIDER: S-EPMC5527112 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature