Han Jiangchao, Shen Jimei, Gao Guoying
School of Physics, Huazhong University of Science and Technology Wuhan 430074 China
Nanjing Normal University Taizhou College Taizhou 225300 China.
RSC Adv. 2019 Jan 25;9(7):3550-3557. doi: 10.1039/c8ra08107g.
Half-metallic ferromagnetic CrO has attracted much interest due to its 100% spin polarization and high Curie temperature. CrO films have been fabricated on a TiO (100) substrate. However, there have been no reports on the spin transport properties of devices based on a CrO electrode and TiO barrier. In this work, we use first-principles calculations combined with a nonequilibrium Green's function method to investigate the bias-voltage-dependent spin transport properties for the CrO/TiO (100) heterostructure and the CrO/TiO/CrO (100) magnetic tunnel junction (MTJ). Our results reveal the excellent spin filtering effect and spin diode effect in the heterostructure as well as the high tunnel magnetoresistance ratio (up to 4.48 × 10%) in the MTJ, which indicate potential spintronic applications. The origins of these perfect spin transport characteristics are discussed in terms of the calculated spin-dependent electrode band structures, the spin-dependent transmission spectra and semiconductor theory.
半金属铁磁体CrO因其100%的自旋极化率和高居里温度而备受关注。CrO薄膜已被制备在TiO(100)衬底上。然而，尚无关于基于CrO电极和TiO势垒的器件自旋输运特性的报道。在这项工作中，我们使用第一性原理计算结合非平衡格林函数方法，研究了CrO/TiO(100)异质结构和CrO/TiO/CrO(100)磁性隧道结(MTJ)的偏置电压依赖自旋输运特性。我们的结果揭示了异质结构中优异的自旋过滤效应和自旋二极管效应，以及MTJ中高达4.48×10%的高隧道磁电阻比，这表明其具有潜在的自旋电子学应用。根据计算得到的自旋相关电极能带结构、自旋相关传输谱和半导体理论，讨论了这些完美自旋输运特性的起源。
