Non-local carrier injection/detection schemes lie at the very foundation of information manipulation in integrated systems. This paradigm consists in controlling with an external signal the channel where charge carriers flow between a "source" and a well separated "drain". The next generation electronics may operate on the spin of carriers instead of their charge and germanium appears as the best hosting material to develop such a platform for its compatibility with mainstream silicon technology and the long electron spin lifetime at room temperature. Moreover, the energy proximity between the direct and indirect bandgaps allows for optical spin injection and detection within the telecommunication window. In this letter, we demonstrate injection of pure spin currents (\textit{i.e.} with no associated transport of electric charges) in germanium, combined with non-local spin detection blocks at room temperature. Spin injection is performed either electrically through a magnetic tunnel junction (MTJ) or optically, exploiting the ability of lithographed nanostructures to manipulate the distribution of circularly-polarized light in the semiconductor. Pure spin current detection is achieved using either a MTJ or the inverse spin-Hall effect (ISHE) across a platinum stripe. These results broaden the palette of tools available for the realization of opto-spintronic devices.
Electrical spin injection and detection in Germanium using three terminal geometry
在这封信中，我们报告成功的电自旋注入和检测\textit{n}型绝缘体上锗（GOI）使用Co/Py/Al $_{2}$ O $_{3}$自旋注入器和3端非本地测量。我们观察到一个增强的自旋积累信号的顺序为1毫电子伏的顺序隧穿过程通过界面状态附近的Al $_{2}$ O $_{3}$ /Ge接口。该自旋信号在高达220 K时可进一步观察到。此外，强的\textit{inverted} Hanle效应的存在表明，注入自旋受到界面粗糙度引起的随机场的影响。
Ultrafast Spin Injection in Graphene via Dynamical Carrier Filtering at Transition Metal Dichalcogenide Interfaces
Kansai Institute for Photon Science, National Institutes for Quantum Science and Technology (QST)（光子科学关西研究所，量子科学技术研究开发机构）；Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo（东京大学大学院工学系研究科核工程与管理学专业）
Quantum Transport in Two-Dimensional WS$_2$ with High-Efficiency Carrier Injection Through Indium Alloy Contacts
二维过渡金属二硫属化合物（TMDCs）具有光电子和量子化学等方面的重要应用。器件的关键元件是金属-半导体界面。然而，高接触电阻阻碍了进展。量子输运研究很少，因为低质量的接触在低温下很难处理。在这里，依赖于温度的转移长度测量进行化学气相沉积生长的单层和双层WS $_2$设备与铟合金接触。该器件具有低接触电阻和肖特基势垒高度（\sim 10 k $Ω$ \si{\micro\metre}在3 K和1.7毫电子伏）。有效的载流子注入能够实现高载流子迁移率（$\sim$ 190 cm $^2$ V $^{-1}$ s $^{-1}$）和共振隧穿的观察。密度泛函理论计算提供了深入了解量子输运和性能的WS $_2$铟接口。我们的研究结果揭示了使用铟合金触点的高性能WS $_2$器件的显著进步。
Anisotropic Photostriction and Strain-modulated Carrier Lifetimes in Orthorhombic Semiconductors
National Center for Nanoscience and Technology, Chinese Academy of Sciences（中国科学院国家纳米科学中心）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；Songshan Lake Materials Laboratory（松山湖材料实验室）
