Coherent propagation of spin helices in a quantum-well confined electron gas.
Coherent propagation of spin helices in a quantum-well confined electron gas.
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自旋螺旋在量子阱限制电子气中的相干传播。
DOI：
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发表时间：
2012
影响因子：
8.6
通讯作者：
Michael Lilly
中科院分区：
文献类型：
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作者：
Luyi Yang;J. Koralek;J. Orenstein;D. Tibbetts;J. Reno;Michael Lilly
我们利用相位分辨瞬态光栅光谱测量了面内电场作用下高迁移率n-GaAs/AlGaAs量子阱中自旋螺旋的传播。在相对较低的领域，螺旋模式交叉从过阻尼激发的自旋进动周期超过自旋寿命，相干传播的制度，可以观察到几个自旋进动周期。我们证明了在70 V cm（-1）的外加电场中，自旋极化包的包络达到10（7）cm s（-1）的电流驱动速度.
We use phase-resolved transient grating spectroscopy to measure the propagation of spin helices in a high mobility n-GaAs/AlGaAs quantum well with an applied in-plane electric field. At relatively low fields helical modes crossover from overdamped excitations where the spin-precession period exceeds the spin lifetime, to a regime of coherent propagation where several spin-precession periods can be observed. We demonstrate that the envelope of a spin polarization packet reaches a current-driven velocity of 10(7) cm s(-1) in an applied field of 70 V cm(-1).