Study of the Magnetic/Charge Structure in SrFeO2.81 Using Resonant Soft X-ray Diffraction
S.H. Lee1*, Y.C. Lai1, S.H. Cheng1, C.W. Hsu1, F. C. Chou2, C.H. Du1
1Departament of Physics, Tamkang University, Tamsui 25137, Taiwan
2Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
* presenting author:李書翰,
We report the study of the charge and spin modulations of SrFeO2.81 using soft x-ray resonant scattering. The oxygen deficient iron-based oxides SrFeO3-δ exhibit a rich and complicated phase diagram, which is closely related to the valence states of Fe. Using soft x-ray scattering at the L-edge of Fe in a high quality single crystal of SrFeO2.81. we identify the origin of the modulated reflection, Qso (0 0 0.5), with a transition temperature of about 60 K, to be magnetic in nature and also in accord with magnetization measurement. Through measurements with different polarized x-rays, we also discovered that the magnetic structure is chiral around the c-axis. In addition, we also observed the charge modulation with a q-wavevector of about 0.36 c* using the soft and hard x-ray measurements. The charge modulation has a transition temperature of about 110 K, and shows a unusual behavior at about 60 K which suggests a strong coupling between the spin, charge, and lattice.

Keywords: Resonant Soft X-ray Diffraction, Magnetic and Charge Structure, SrFeO3-x