We report a high resolution neutron diffraction investigation of the coupling of structural and magnetic transitions in Ba1-xK xFe2As2. The tetragonal-orthorhombic and antiferromagnetic transitions are suppressed with potassium doping, falling to zero at x Fe1-xCox)2As2, the two transitions are first order and coincident over the entire phase diagram, with a biquadratic coupling of the two order parameters. The phase diagram is refined showing that the onset of superconductivity is at x=0.133 with all three phases coexisting until x≤0.24.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - May 27 2011|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics