Key Laboratory of Quantum Information, University of Science and Technology of China, Chinese Academy of Sciences, Hefei 230026, People's Republic of China.
Nano Lett. 2010 Aug 11;10(8):2956-60. doi: 10.1021/nl101181e.
We investigate the low-temperature magneto-transport properties of individual Ge/Si core/shell nanowires. Negative magneto-conductance was observed, which is a signature of one-dimensional weak antilocalization of holes in the presence of strong spin--orbit coupling. The temperature and back gate dependences of phase coherence length, spin--orbit relaxation time, and background conductance were studied. Specifically, we show that the spin--orbit coupling strength can be modulated by more than five folds with an external electric field. These results suggest the Ge/Si nanowire system possesses strong and tunable spin--orbit interactions and may serve as a candidate for spintronics applications.
我们研究了单个 Ge/Si 核壳纳米线的低温磁输运性质。观察到了负磁导率，这是在强自旋轨道耦合存在下，空穴一维弱反局域的特征。研究了相位相干长度、自旋轨道弛豫时间和背景电导随温度和背栅的变化。具体来说，我们表明可以通过外加电场将自旋轨道耦合强度调节超过五倍。这些结果表明 Ge/Si 纳米线系统具有强且可调谐的自旋轨道相互作用，可能成为自旋电子学应用的候选材料。
