Chen Y Z, Sun J R, Zhao J L, Wang J, Shen B G, Pryds N
State Key Laboratory of Magnetism, Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. Fuel cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark, DK-4000 Roskilde, Denmark.
J Phys Condens Matter. 2009 Nov 4;21(44):442001. doi: 10.1088/0953-8984/21/44/442001. Epub 2009 Oct 9.
We investigated the structure and magnetotransport properties of Sm(0.5)Ca(0.5)MnO(3) (SCMO) films epitaxially grown on (011)-oriented SrTiO(3) substrates, which exhibited clear charge/orbital ordering transition. A significant anisotropy of ∼1000 in the colossal magnetoresistance (CMR) effect was observed in the films with a thickness between 50 and 80 nm, which was distinctly different from the basically isotropic CMR effect in bulk SCMO. The large anisotropy in the CMR can be ascribed to the intrinsic asymmetric strain in the film, which plays an important role in tuning the spin-orbit coupling in manganite films. The origin of the peculiar CMR effect is discussed.
我们研究了在（011）取向的SrTiO₃衬底上外延生长的Sm(0.5)Ca(0.5)MnO₃（SCMO）薄膜的结构和磁输运性质，这些薄膜表现出明显的电荷/轨道有序转变。在厚度为50至80纳米的薄膜中观察到巨磁电阻（CMR）效应存在约1000的显著各向异性，这与块状SCMO中基本各向同性的CMR效应明显不同。CMR中的大各向异性可归因于薄膜中固有的不对称应变，其在调节锰氧化物薄膜中的自旋 - 轨道耦合方面起着重要作用。文中讨论了这种特殊CMR效应的起源。
