Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742, USA and Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627, USA.
Department of Physics and Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742, USA.
Phys Rev Lett. 2013 Dec 20;111(25):257204. doi: 10.1103/PhysRevLett.111.257204. Epub 2013 Dec 18.
A unique spin depolarization mechanism, induced by the presence of g-factor anisotropy and intervalley scattering, is revealed by spin-transport measurements on long-distance germanium devices in a magnetic field longitudinal to the initial spin orientation. The confluence of electron-phonon scattering (leading to Elliott-Yafet spin flips) and this previously unobserved physics enables the extraction of spin lifetime solely from spin-valve measurements, without spin precession, and in a regime of substantial electric-field-generated carrier heating. We find spin lifetimes in Ge up to several hundreds of nanoseconds at low temperature, far beyond any other available experimental results.
通过在磁场中对沿初始自旋方向纵向的长距离锗器件进行自旋输运测量，揭示了一种由 g 因子各向异性和谷间散射引起的独特的自旋去极化机制。电子-声子散射（导致 Elliott-Yafet 自旋翻转）与这种以前未观察到的物理现象的结合，使得自旋寿命能够仅从没有自旋进动的自旋阀测量中提取出来，并在电场产生的载流子加热的大量情况下进行。我们发现，在低温下，Ge 的自旋寿命长达数百纳秒，远远超过任何其他可用的实验结果。
