Inelastic light scattering by intrasubband spin-density excitations in GaAs-AlGaAs quantum wells with balanced Bychkov-Rashba and Dresselhaus spin-orbit interaction: Quantitative determination of the spin-orbit field
Inelastic light scattering by intrasubband spin-density excitations in GaAs-AlGaAs quantum wells with balanced Bychkov-Rashba and Dresselhaus spin-orbit interaction: Quantitative determination of the spin-orbit field
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DOI：
10.1103/physrevb.101.035427
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发表时间：
2020-01
影响因子：
3.7
通讯作者：
S. Gelfert;C. Frankerl;C. Reichl;D. Schuh;G. Salis;W. Wegscheider;D. Bougeard;T. Korn;C. Schüller
中科院分区：
文献类型：
--
作者：
S. Gelfert;C. Frankerl;C. Reichl;D. Schuh;G. Salis;W. Wegscheider;D. Bougeard;T. Korn;C. Schüller
利用非弹性光散射实验研究了面内外磁场作用下调制掺杂GaAs-AlGaAs单量子威尔斯（001）阱中低能子带内自旋密度激发（SDEs）.所研究的样品在两种不同的组态中具有平衡的线性Bychkov-Rashba（α）和Dresselhaus（β）自旋轨道强度，α=β和α=−β。这两种配置导致导带的自旋分裂的极端各向异性，其中两种配置的最大自旋分裂的面内方向彼此垂直。自旋分裂的不对称性可以直接检测通过时间反转对称性的破坏，由于在量子阱平面中的动量q的转移，通过双折射。此外，面内磁场Bext q的应用允许我们调制有效磁场。通过对实验谱线的数值线形分析，我们确定了样品的相关参数。我们发现线性自旋轨道强度|α| =β对于两个样品是相当的，而电子g因子是明显不同的。此外，我们实验量化的最大内部自旋轨道场的值，这是高达BSO 18 T的两个样品。
Inelastic light scattering experiments on low-energy intrasubband spin-density excitations (SDEs) are performed in (001)-grown modulation-doped GaAs-AlGaAs single quantum wells in in-plane external magnetic fields. The investigated samples possess balanced linear Bychkov-Rashba (α) and Dresselhaus (β) spin-orbit strengths in two different configurations, α=β and α=−β. Both configurations lead to an extreme anisotropy of the spin splitting of the conduction band, where the in-plane directions of maximum spin splitting for both configurations are perpendicular to each other. The spin splitting asymmetry can be directly detected via the SDE by breaking of the time-reversal symmetry due to transfer of a momentum q in the quantum-well plane. In addition, the application of an in-plane magnetic field Bext⊥q allows us to modulate the effective magnetic field. Via a numerical line-shape analysis of the experimental SDE spectra, we determine the relevant parameters of the samples. We find that the linear spin-orbit strength |α|=β is comparable for both samples, while the electron g factors are markedly different. Furthermore, we experimentally quantify the values of the maximum internal spin-orbit fields, which are as high as Bso∼18T for both samples.