Magnetic phase transition and magnetic structures in SmBaMnO

Kiyanagi, Ryoji  ; Yamada, Shigeki*; Aoki, Hiroshi*; Sagayama, Hajime*; Moyoshi, Taketo*; Nakao, Akiko*; Arima, Takahisa*

Manganites with perovskite-type structure have been attracted much attention because of their variety of orders and properties due to the competition between charges, orbitals and spins. The materials represented as ReBaMnO forms in an A-site ordered double perovskite structure and exhibit complicated phase diagrams depending on the kind of atoms of Re. In the case of Re = Sm, the material shows two charge-orbital orders and two anomalies in magnetic susceptibility, but the details have not been clarified. In this study, the magnetic structure in the antiferromagnetic phase and the relation between the charge-orbital order and the antiferromagnetic phase were investigated by means of neutron magnetic scattering. The measurements were performed on the single crystal neutron diffractometer, SENJU, at J-PARC/MLF. The diffraction pattern revealed magnetic reflections arising from the antiferromagnetic order, which is consistent with the charge-orbital ordering patterns. In addition, the anomaly at the lowest temperature was found due to the reorientation of the spin moments.