Systematic electrical transport characterizations were performed on high-quality Bi2O2Se nanowires to illustrate its great transport properties and further application potentials in spintronics. Bi2O2Se nanowires synthesized by chemical vapor deposition method presented a high field-effect mobility up to 1.34*104 cm2V-1s-1, and exhibited ballistic transport in the low back-gate voltage (Vg) regime where conductance plateaus were observed. When further increasing the electron density by increasing Vg, we entered the phase coherent regime and weak antilocalization (WAL) was observed. The spin relaxation length extracted from the WAL was found to be gate tunable, ranging from ~100 nm to ~250 nm and reaching a stronger spin-obit coupling (SOC) than the two-dimensional counterpart (flakes). We attribute the strong SOC and the gate tunability to the presence of a surface accumulation layer which induces a strong inversion asymmetry on the surface. Such scenario was supported by the observation of two Shubnikov-de Haas oscillation frequencies that correspond to two types of carriers, one on the surface, and the other in the bulk. The high-quality Bi2O2Se nanowires with a high mobility and a strong SOC can act as a very prospective material in future spintronics.
研究了InSb纳米线的低温电子迁移率。我们提取的迁移率在4.2开尔文通过场效应传输测量使用一个模型组成的接触电阻的三极管。该模型能够准确提取器件参数，从而可以系统地研究纳米线的迁移率。我们确定影响迁移率的因素，并优化后获得$\sim2.5\mathbin{\times}10^4$ cm $^2$ /Vs的场效应迁移率。我们进一步证明了这些迁移率值的再现性，这是最高的纳米线报道。我们的调查表明，目前的流动性是有限的吸附分子的纳米线表面和/或基板。
Carrier Transport in High Mobility InAs Nanowire Junctionless Transistors
理解和模拟纳米线晶体管性能极限的能力是设计下一代器件的关键。在这里，我们报告的高迁移率结无栅全包围纳米线场效应晶体管的载流子迁移率在室温下达到2000 cm 2/V.s的研究。依赖于温度的运输测量揭示了激活运输在低温下由于表面捐助者，而在室温下的运输表现出扩散行为。从电导率数据中，提取的值的声速在InAs纳米线被发现是一个顺序小于散装。这种低声速归因于普遍出现在这些纳米线中的扩展的晶体缺陷。分析温度相关的迁移率数据，我们确定了关键的散射机制限制在这些纳米线的载流子传输。最后，使用这些散射模型，我们进行漂移扩散的纳米线场效应晶体管的输运模拟和比较与实验测量的设备性能。我们的器件建模提供了深入了解InAs纳米线晶体管的性能限制，并可用作基于MEMS的集成电路的预测方法。
Giant thermovoltage in single InAs-nanowire field-effect transistors
毫伏范围的热电压证明在单一的InAs纳米线的场效应晶体管。由于埋入式加热方案，我们驱动大的热偏压DT> 10 K和纳米结构上的电导的强场效应调制。这使得精确映射的Seebeck系数S的演变作为室温和100 K $之间的门控电导率的函数。基于这些实验数据的电子迁移率的一个新的估计。这个值进行了比较，与标准的场效应为基础的迁移率估计的结果和讨论有关的设备中的电荷陷阱的效果。
Gate-all-around nanowire transistor, due to its extremely tight electrostatic control and vertical integration capability, is a highly promising candidate for sub-5 nm technology node. In particular, the junctionless nanowire transistors are highly scalable with reduced variability due to avoidance of steep source/drain junction formation by ion implantation. Here we demonstrate a dual-gated junctionless nanowire \emph{p}-type field effect transistor using tellurium nanowire as the channel. The dangling-bond-free surface due to the unique helical crystal structure of the nanowire, coupled with…
High quality heteroepitaxial two-dimensional (2D) InSb layers are very difficult to realize owing to the large lattice mismatch with other widespread semiconductor substrates. A way around this problem is to grow free-standing 2D InSb nanostructures on nanowire (NW) stems, thanks to the capability of NWs to efficiently relax elastic strain along the sidewalls when lattice-mismatched semiconductor systems are integrated. In this work, we optimize the morphology of free-standing 2D InSb nanoflags (NFs). In particular, robust NW stems, optimized growth parameters, and the use of reflection high-e…
Quantifying Strain and its Effect on Charge Transport in Ge/Si Core/Shell Nanowires
University of Basel（巴塞尔大学）；Swiss Nanoscience Institute, University of Basel（瑞士纳米科学研究所，巴塞尔大学）；Institut de Ciència de Materials de Barcelona, ICMAB–CSIC（巴塞罗那材料科学研究所，ICMAB-CSIC）
Advances in quantum technology may come from the discovery of new materials systems that improve the performance or allow for new functionality in electronic devices. Lead telluride (PbTe) is a member of the group IV-VI materials family that has significant untapped potential for exploration. Due to its high electron mobility, strong spin-orbit coupling and ultrahigh dielectric constant it can host few-electron quantum dots and ballistic quantum wires with opportunities for control of electron spins and other quantum degrees of freedom. Here, we report the fabrication of PbTe nanowires by mole…
Effects of phonon confinement on electron transport in Si nanowire and armchair-edge graphene nanoribbon transistors: A dissipative quantum-transport study
Universal features of phonon transport in nanowires with correlated surface roughness
在有意粗糙化的硅纳米线（SiNW）中实验观察到的超低热导率$κ$在声子蒙特卡罗模拟中再现，其中指数相关的真实空间粗糙表面类似于测量[J.Lim，K. Hippalgaonkar，S. C. Andrews，A. Majumdar和P. Yang，Nano Lett. 12，2475（2012）]。通用功能的热输运揭示$κ$作为一个功能的归一化几何平均自由程$\barλ$（$0<\barλ<1$）的扩散（Casimir）限制对应于$\barλ=1/2$。$κ$与$\barλ$在低至中等粗糙度（高$\barλ$）下呈指数关系，其中内部散射随机中断声子在SiNW上的反弹，而在高粗糙度（低$\barλ$）下呈线性关系，其中同一表面处的多次散射事件导致超低的非晶极限热导率。
Recent advances in the growth of III-V semiconductor nanowires (NWs) hold great promise for nanoscale optoelectronic device applications. Recently, it was found that a small amount of nitrogen (N) incorporation in III-V semiconductor NWs can effectively red-shift their wavelength of operation and tailor their electronic properties for specific applications. However, understanding the impact of N incorporation on non-equilibrium charge carrier dynamics and transport in semiconducting NWs is critical in achieving efficient semiconducting NW devices. In this work, ultrafast optical pump-terahertz…
Quantized Conductance through Surface States in High Quality Three-Dimensional Dirac Semimetal Cd$_3$As$_2$ Nanowire/Nanoribbon p-n Junctions
DGIST Research Institute, DGIST（大邱科学技术院研究学院）；Electrical and Computer Engineering, National University of Singapore（新加坡国立大学电气与计算机工程系）；Department of Physics, KTH Royal Institute of Technology（皇家理工学院物理系）；Industrial AX Innovation Research Institute and Sensor Technology Support Center, DGIST（大邱科学技术院工业AX创新研究所及传感器技术支持中心）；Department of Advanced Materials Chemistry, Korea University（韩国大学先进材料化学系）；Department of Physics and Chemistry, DGIST（大邱科学技术院物理化学系）；Department of Interdisciplinary Engineering, DGIST（大邱科学技术院交叉工程学系）；Institute of next generation semiconductor technology (INST), DGIST（大邱科学技术院下一代半导体技术研究所）
We have used a polarized microluminescence technique to investigate photocarrier charge and spin transport in n-type depleted GaAs nanowires ($ \approx 10^{17}$ cm$^{-3}$ doping level). At 6K, a long-distance tail appears in the luminescence spatial profile, indicative of charge and spin transport, only limited by the length of the NW. This tail is independent on excitation power and temperature. Using a self-consistent calculation based on the drift-diffusion and Poisson equations as well as on photocarrier statistics (Van Roosbroeck model), it is found that this tail is due to photocarrier d…
Quantum-classical dynamics of Rashba spin-orbit coupling
Instytut Matematyki Uniwersytet Gdański（格但斯克大学数学研究所）；Université de Strasbourg CNRS Institut de Physique et Chimie des Matériaux de Strasbourg（斯特拉斯堡大学法国国家科学研究中心斯特拉斯堡材料物理与化学研究所）；School of Mathematics Physics University of Surrey（萨里大学数理学院）；School of Physical Mathematical Sciences Nanyang Technological University（南洋理工大学物理与数理科学学院）
