TY  - JOUR
AU  - Waßer, F.
AU  - Schneidewind, A.
AU  - Sidis, Y.
AU  - Wurmehl, S.
AU  - Aswartham, S.
AU  - Büchner, B.
AU  - Braden, M.
TI  - Spin reorientation in Ba $_{0.65}$ Na $_{0.35}$ Fe $_{2}$ As $_{2}$ studied by single-crystal neutron diffraction
JO  - Physical review / B
VL  - 91
IS  - 6
SN  - 1098-0121
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2015-03054
SP  - 060505
PY  - 2015
AB  - We have studied the magnetic ordering in Ba1−xNaxFe2As2 with 0.25≤x≤0.4 by unpolarized and polarized neutron diffraction using single crystals. Unlike most FeAs-based compounds that magnetically order, Na-doped BaFe2As2 exhibits two successive magnetic transitions: For x=0.35, upon cooling, magnetic order occurs at ∼70 K with in-plane magnetic moments being arranged as in pure or Ni-, Co-, or K-doped BaFe2As2 samples. At a temperature of ∼46 K a second phase transition occurs, which the single-crystal neutron-diffraction experiments can unambiguously identify as a spin reorientation. At low temperatures, the ordered magnetic moments in Ba0.65Na0.35Fe2As2 point along the c direction. The two nearly degenerate magnetic states document orbital degeneracy to persist in the superconducting phase.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000350251500001
DO  - DOI:10.1103/PhysRevB.91.060505
UR  - https://juser.fz-juelich.de/record/190096
ER  -