Competition between ferromagnetism and antiferromagnetism in FePt

作     者：G. Brown B. Kraczek A. Janotti T. C. Schulthess G. M. Stocks D. D. Johnson 

作者机构：Center for Computational Sciences Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Computer Science and Mathematics Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA School of Computational Science and Information Technology Florida State University Tallahassee Florida 32306 USA Departments of Physics and Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA Metals and Ceramics Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2003年第68卷第5期

页      面：052405-052405页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

摘      要：FePt in the L10 (tetragonal) phase is of interest due to its ease of synthesis as nanoparticles and because superparamagnetism is suppressed by the large magnetoanisotropy energy (MAE) of the L10 phase. Here we present the results of first-principles electronic-structure calculations that reveal a competition between ferromagnetic (FM) and antiferromagnetic (AFM) ordering of the alternating Fe planes, with energy differences less than room-temperature thermal energy. We find that the FM state is stabilized relative to the AFM state as L10 tetragonal distortion decreases or chemical (antisite) disorder increases on Pt planes. Inherently, then, there is a competition between stabilizing the FM state and maintaining the large MAE in FePt, and optimally maximizing both is important for nanomagnetic applications.