Study of the dependence of the magnetic moment of La_1−xSr_xMnO₃ on the Sr doping level x

¹ Hebei Advanced Thin Film Laboratory, Department of Physics, Hebei Normal University Shijiazhuang City, 050024, PRC
² Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for Nanotechnology, Nanjing University Nanjing, 210093, PRC
³ State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences Beijing 100190, PRC

^(a) tanggd@mail.hebtu.edu.cn (corresponding author)

Received: 23 September 2017
Accepted: 11 December 2017

Abstract

The dependence of the magnetic moment of the perovskite manganites La_1−xSr_xMnO₃ on the Sr doping level, x, is fitted using an oxygen 2p itinerant electron model for magnetic oxides (i.e., the IEO model), which is similar to the O 2p hole model proposed by Alexandrov et al. (Phys. Rev. Lett., 96 (2006) 117003). According to this IEO model, the itinerant electrons in these manganites are oxygen 2p electrons (or 2p holes) rather than 3d electrons, as assumed in the double-exchange interaction model. Furthermore, the proposed IEO model describes the process by which the itinerant electrons transit along the O²⁻–Mn²⁺–O²⁻–Mn³⁺–O¹⁻ ion chains in La_1−xSr_xMnO₃ (x < 0.15), wherein a 2p hole is present in the outer orbit of the O¹⁻ anion and the magnetic moment of the Mn³⁺ cation is opposite to that of the Mn²⁺ cation.