Structural investigation of magnetocapacitive SmMnO

Maeda, Hiroki*; Ishiguro, Yuki*; Honda, Takashi*; Jung, J.-S.*; Michimura, Shinji*; Inami, Toshiya; Kimura, Tsuyoshi*; Wakabayashi, Yusuke*

Structural deformation of a magnetocapacitive material SmMnO was studied by X-ray diffraction measurement in a magnetic field. This antiferromagnetic material shows a jump in dielectric constant at 9 K only when a magnetic field of a few tesla is applied. In-field X-ray diffraction measurements clarified that there is no sudden change in structure that involves atomic displacement within the c-plane in Pbnm notation, while the antiferromagnetic phase transition at 60 K gives rise to a noticeable rotation of the MnO octahedra. This rotation occurs to maximize the energy gain through the exchange interaction.