Fragile Magnetic Ground State in Half-Doped LaSr2Mn2O7

作     者：J.-S. Lee C.-C. Kao C. S. Nelson H. Jang K.-T. Ko S. B. Kim Y. J. Choi S.-W. Cheong S. Smadici P. Abbamonte J.-H. Park 

作者机构：Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory Menlo Park California 94025 USA National Synchrotron Light Source Brookhaven National Laboratory Upton New York 11973 USA c-CCMR and Department of Physics Pohang University of Science and Technology Pohang 790-784 South Korea Advancement for College Education Center Konyang University Chungnam 320-711 South Korea R-CEM and Department of Physics and Astronomy Rutgers University Piscataway New Jersey 08854 USA l-PEM and Department of Physics Pohang University of Science and Technology Pohang 790-784 South Korea Physics Department and Frederick Seitz Materials Research Laboratory University of Illinois Urbana Illinois 61801 USA Division of Advanced Materials Science Pohang University of Science and Technology Pohang 790-784 South Korea 

出 版 物：《Physical Review Letters》 (Phys Rev Lett)

年 卷 期：2011年第107卷第3期

页      面：037206-037206页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Office of Basic Energy Sciences, U.S. DOE [DE-FG02-06ER46285] NSLS [DE-AC02-98CH10886] MEST [2009-0081576, R31-2008-000-10059-0, 2010-00471] POSTECH MOST 

主　　题：X ray scattering 

摘      要：We investigated the orbital and antiferromagnetic ordering behaviors of the half-doped bilayer manganite La2−2xSr1+2xMn2O7 (x≃0.5) by using Mn L2,3-edge resonant soft x-ray scattering. Resonant soft x-ray scattering reveals the CE-type orbital order below Too≃220 K, which shows partial melting behavior below Tm≃165 K. We also found coexistence CE- and A-type antiferromagnetic orders. Both orders involve the CE-type orbital order with nearly the same orbital character and are coupled with each other. These results manifest that the ground state with the CE-type antiferromagnetic order is easily susceptible to destabilization into the A-type one even with a small fluctuation of the doping level, as suggested by the extremely narrow magnetic phase boundaries at x≃0.5±0.005.