We studied the family of high-temperature iron-based superconductors NaxFeAs characterized by different sodium content. We found out that under 45 K all members of the family undergo a transition into the spin-density wave magnetic ordered state, where the portion of the Fermi surface remains gapless. This portion is directly related to the superconducting fraction as deduced from bulk susceptibility under 12 K. Our findings are consistent with the theories of coexisting magnetic order and superconductivity.
COBISS.SI-ID: 24952103
Copper oxides fascinate with a plethora of exotic electronic ground states, including high-temperature superconductivity and quantum magnetism. CuNCN is a nitrogen-containing analog of cupric oxide, in which the magnetism is surprisingly suppressed. Local-probe studies including muon spin relaxation, electron spin resonance and nuclear magnetic resonance have shown that magnetic ordering is missing in this system down to the lowest experimentally accessible temperatures and that the magnetism is inhomogeneous.
COBISS.SI-ID: 24909863