Nozaki T, Tezuka N, Inomata K
Department of Materials Science, Graduate School of Engineering, Tohoku University, Aobayama 6-6-02, Sendai 980-8579, Japan.
Phys Rev Lett. 2006 Jan 20;96(2):027208. doi: 10.1103/PhysRevLett.96.027208. Epub 2006 Jan 19.
We investigated spin-dependent tunneling conductance properties in fully epitaxial double MgO barrier magnetic tunnel junctions with layered nanoscale Fe islands as a middle layer. Clear oscillations of the tunneling conductance were observed as a function of the bias voltage. The oscillation, which depends on the middle layer thickness and the magnetization configuration, is interpreted by the modulation of tunneling conductance due to the spin-polarized quantum well states created in the middle Fe layer. This first observation of the quantum size effect in the fully epitaxial double barrier magnetic tunnel junction indicates great potential for the development of the spin-dependent resonant tunneling effect in coherent tunneling regime.
我们研究了以层状纳米级铁岛作为中间层的全外延双氧化镁势垒磁性隧道结中的自旋相关隧穿电导特性。观察到隧穿电导随偏置电压呈现出清晰的振荡。这种依赖于中间层厚度和磁化配置的振荡，可通过中间铁层中产生的自旋极化量子阱态对隧穿电导的调制来解释。在全外延双势垒磁性隧道结中首次观察到的量子尺寸效应，表明在相干隧穿 regime 中自旋相关共振隧穿效应的发展具有巨大潜力。
