Neutron scattering studies on ferroelectric, charge and spin frustrated layered triangular system LuFeO

Kakurai, Kazuhisa; Ikeda, Naoshi*; Nagai, Satoshi*; Matsuda, Masaaki; Ishii, Yoshinobu; Owada, Kenji; Inami, Toshiya; Yoshii, Kenji  ; Murakami, Yoichi*; Kito, Hijiri*; Yamada, Yasusada*

The observation of an anomalous magnetic ordering process in the charge ordered LuFeO by means of neutron scattering is reported. The neutron scattering experiments were performed on TAS-1 and TAS-2 instruments installed at JAEA-JRR-3. Despite the triangular configuration a strong 2-D antiferromagnetic correlation with ferrimagnetic component in the double layer in the hexagonal plane develops to a 3-D order along the c-axis at T=242K. At around 177K another characteristic temperature T was discovered where new type of broad magnetic peaks start to grow and at the same time the magnetic peaks already developed below T also acquire finite line width, including the peaks due to the ferrimagnetic component. Field dependence of T was investigated. Upon applying the field perpendicular to the layer plane, T decreases and vanishes above 3T. The existence of the anomalous magnetic ground state will be demonstrated and discussed.