We report a comprehensive investigation of the magnetic properties of LuFe2O4 (LFO) samples with different oxygen stoichiometries. Samples with excess oxygen exhibit spin glass behavior without long-range magnetic order, while three-dimensional ferrimagnetic order exists in a stoichiometric sample. Dissimilar experimental observations reported in several papers can be understood consistently when oxygen stoichiometry is taken into account. The stoichiometric sample orders magnetically below TN = 243 K, and a monoclinic lattice distortion sets in below TL = 175 K. This structural change is sensitive to the applied magnetic field, indicating strong spin-lattice coupling in this material. Unusual low-field thermal magnetization behavior was observed near TL, and its origin is discussed.
Bibliographical noteFunding Information:
We would like to thank K. S. Burch, J. P. Clancy, G. Xu, and S. M. Shapiro for valuable discussions and comments. Research at the University of Toronto was supported by the Natural Science and Engineering Research Council of Canada, Canadian Foundation for Innovation, and Ontario Ministry of Research and Innovation. Y. Lee thanks the support from the Global Research Laboratory of the National Research Foundation of Korea. The experiment at PAL was supported in part by the MEST (Korea) and POSTECH. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)