Room temperature multiferroic properties of Mn doped La2Ti2O7
Polycrystalline La2Ti2-xMnxO7 (LTMO) (x = 0−0.16) ceramics fabricated by the conventional solid-state reaction are utilized to investigate the effect of Mn doping on the ferroelectric (FE) and ferromagnetism (FM) systematically. Both the FE and FM properties strongly depend on the doping level of Mn atoms, which directly induces a structural phase transition from monoclinic to orthorhombic. Compared with pure La2Ti2O7 (LTO), remnant polarization decreases sharply with the doping level at first, and slightly increases when x ≥ 0.08, which is proposed to result from the evolution oxygen vacancies. All the doped samples exhibit weak FM property at room temperature, until the maximum can be observed for x = 0.08. Mn3+-Mn4+ double-exchange and anti-FM Mn3+-Mn3+ and Mn4+-Mn4+ super-exchange interactions are responsible for the different ferromagnetic behavior of LTMO.
KeywordsMultiferroic properties La2Ti2O7 Phase transformation Oxygen vacancy
This work was supported by the National Science Foundation of China (Grant No. 11174092). Helpful discussions with Dr. L. H. Qian are appreciated. We would also like to thank the staff of Analysis Center of HUST for their assistance in various measurements.
- 20.W.S. Kim, S.M. Ha, S. Yun, H.H. Park, Thin Solid Films 420–421, 575 (2002)Google Scholar