Quantitative analysis of the weak anti-localization effect in ultrathin bismuth films
Quantitative analysis of the weak anti-localization effect in ultrathin bismuth films
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DOI：
10.1209/0295-5075/95/37002
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发表时间：
2011-08
期刊：
影响因子：
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通讯作者：
S. Sangiao;N. Marcano;J. Fan;L. Morellón;M. Ibarra;J. M. Teresa
中科院分区：
文献类型：
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作者：
S. Sangiao;N. Marcano;J. Fan;L. Morellón;M. Ibarra;J. M. Teresa
测量了外加磁场高达9T、垂直于薄膜平面和平行于薄膜平面的磁场对超薄膜电导率的影响，并用二维体系中的弱反局域化理论对其进行了分析。随着薄膜厚度的减小，经典磁阻效应被完全抑制，只观察到微弱的反局域化效应。从分析中提取的参数可以用来研究不同的散射机制对超薄Bi膜电子输运性质的贡献。特别是，与厚度无关的自旋-轨道散射长度表明，在超薄膜极限范围内，自旋-轨道分裂表面态主导着输运。
Magnetic-field dependence of conductivity in ultrathin Bi films is measured in applied magnetic fields up to 9 T, in both directions, perpendicular and parallel to the film plane, at temperatures down to 0.4 K, and analyzed in terms of the weak anti-localization theory in two-dimensional systems. With the reduction of film thickness, the classical magnetoresistance effect is completely suppressed, and only the weak anti-localization effect is observed. The parameters extracted from the analysis allow the study of the contribution of the different scattering mechanisms to the electronic transport properties in ultrathin Bi films. In particular, the thickness-independent spin-orbit scattering length indicates that the spin-orbit split surface states dominate the transport in the ultrathin-film limit.