Terahertz quantum Hall effect for spin-split heavy-hole gases in strained Ge quantum wells
Terahertz quantum Hall effect for spin-split heavy-hole gases in strained Ge quantum wells
复制标题
DOI：
10.1088/1367-2630/18/11/113036
复制
发表时间：
2016-11-21
影响因子：
3.3
通讯作者：
Lloyd-Hughes, J.
中科院分区：
文献类型：
--
作者：
Failla, M.;Keller, J.;Lloyd-Hughes, J.
采用偏振分辨太赫兹时域光谱技术对应变锗量子阱威尔斯中自旋分裂重空穴气体进行了表征。有效质量，载流子密度，g-因子，运输寿命，迁移率和Rashba自旋分裂能量进行了评估，定量的洞察应变的影响。双轴压应变越大，Rashba系数越低，而在3 K时，重空穴迁移率提高到1.5 x 10（6）cm（2）V-1 s（-1）以上。这种高迁移率使得在太赫兹频率下观察自旋分裂二维重空穴的光量子霍尔效应成为可能，这在偶数和奇数填充因子下的横向磁导率中表现为平台。
Spin-split heavy-hole gases in strained germanium quantum wells were characterized by polarisation-resolved terahertz time-domain spectroscopy. Effective masses, carrier densities, g-factors, transport lifetimes, mobilities and Rashba spin-splitting energies were evaluated, giving quantitative insights into the influence of strain. The Rashba coefficient was found to lower for samples with higher biaxial compressive strain, while heavy-hole mobilities were enhanced to over 1.5 x 10(6) cm(2) V-1 s(-1) at 3 K. This high mobility enabled the observation of the optical quantum Hall effect at terahertz frequencies for spin-split two-dimensional heavy-holes, evidenced as plateaux in the transverse magnetoconductivity at even and odd filling factors.