Spin-orbit scattering time and dephasing time of carriers in two-dimensional HgTe-CdTe superlattices and heterojunctions.
Spin-orbit scattering time and dephasing time of carriers in two-dimensional HgTe-CdTe superlattices and heterojunctions.
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DOI：
10.1103/physrevb.35.5639
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发表时间：
1987-04
期刊：
影响因子：
--
通讯作者：
Moyle;Cheung;Ong
中科院分区：
文献类型：
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作者：
Moyle;Cheung;Ong
报道了HgTe和NdTe异质结中二维电子气的弱局域化研究。由于有效质量很小，扩散常数D非常大(824平方英尺)。厘米/S)。通过对来自高迁移率样品(50,000平方英尺)的弱场横向磁阻数据进行拟合。Cm/vs，R=720欧姆/单位面积。在Hikami，Larkin和Nagoka的计算中，作者确定了自旋-轨道散射时间和载流子退相时间与温度(T)的关系。结果表明，该系统具有主要的自旋轨道散射。(自旋轨道速率是弹性散射率的0.6倍。)退相时间在大小上与Al-tshuler、Aronov和Khmel‘nitskii的计算一致。从阻力与In T的关系图中得到的重要库仑相互作用参数的证据与现有的理论非常不一致。在纵向几何形状上也可以看到显著的反常磁阻。数据与相互作用理论(塞曼分裂)和弱局域化理论进行了比较。还报道了高阻(30千欧姆/单位面积)样品的结果，这表明微扰理论是错误的。
Weak-localization studies of the two-dimensional electron gas in heterostructures made of HgTe adn CdTe are reported. Because of the small effective mass, the diffusion constant D is unusually large (824 sq. cm/s). By fitting the weak-field transverse magnetoresistance data from high-mobility samples (50,000 sq. cm/Vs, R = 720 ohms/unit area to the calculation of Hikami, Larkin, and Nagoka, the authors determined the temperature (T) dependence of the spin-orbit scattering time and the dephasing time of carriers. The system is shown to have dominant spin-orbit scattering. (The spin-orbit rate is 0.6 times the elastic scattering rate.) The dephasing time which is linear in T agrees in magnitude with a calculation by Al-tshuler, Aronov, and Khmel'nitskii. Evidence for significant Coulomb interaction parameter derived from the plot of the resistance versus in T strongly disagrees with existing theories. Prominent anomalous magnetoresistance is also seen in the longitudinal geometry. The data are compared with the interaction theory (Zeeman splitting) and the weak-localization theory. Results from high-resistance (30 kilo ohm/unit area) samples which indicate the breakdown of perturbation theory are also reported.