High-quality nanowires of germanium telluride (GeTe), a one-dimensional chalcogenide phase-change nanostructure, were synthesized via thermal evaporation method under vapor−liquid−solid mechanism. The physical morphology, chemical composition, and crystal structure of the as-synthesized GeTe nanowires were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and X-ray photoemission spectroscopy. Through real-time TEM imaging of nanowire sample heated in an incrementally controllable heating system, the melting point of a single crystalline GeTe nanowire (∼40−80 nm diameter) is found to be significantly lower than that of its bulk counterpart (46% reduction, from 725 to 390 °C). The significant reduction in melting point makes one-dimensional phase-change chalcogenide nanowire a potential material for application in low-power high-density resistive switching nonvolatile data storage in which the thermal energy for material phase transition would be significantly reduced.

Nonvolatile memory device using indium selenide nanowire as programmable resistive element was fabricated and its resistive switching property was studied as functions of electrical pulse width and voltage magnitude. The nanowire memory can be repeatedly switched between high-resistance (∼1011Ω) and low-resistance (∼6×105Ω) states which are attributed to amorphous and crystalline states, respectively. Once set to a specific state, the nanowire resistance is stable as measured at voltages up to 2V. This observation suggests that the nanowire can be programed into two distinct states with a large on-off resistance ratio of ∼105 with significant potential for nonvolatile information storage.

The authors report the synthesis of one-dimensional indium selenide nanowire, a III-VI group compound semiconductor nanostructure with potential applications in data storage, solar cells, and optoelectronics. Nanoscale gold particles were used as catalysts and growth was also demonstrated using indium as self-catalyst. The growth mechanism is confirmed to be vapor-liquid-solid process by in situ heating experiments in which In and Se were found to diffuse back into the gold catalyst bead forming a Au–In–Se alloy that was molten at elevated temperatures. The morphology, composition, and crystal structure of the In2Se3 nanowires (NWs) were analyzed by scanning electron microscopy, energy dispersive x-ray spectroscopy, and high-resolution transmission electron microscopy.

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The calculated electron Hall Mobility and Hall scattering factor in n-type 6H-SiC based on numerical solutions to the Boltzmann transport equation are presented. These results were obtained by solving the Boltzmann equation exactly for the electron Hall mobility using the contraction mapping principle and the electron drift mobility with Rode’s iterative method. The relative importance of the various scattering mechanisms for these calculations is discussed, and a new set of values for the acoustic deformation potential, intervalley deformation potential, and intervalley phonon energy is found, which simultaneously fit experimental Hall mobility and Hall scattering factor data. The calculated Hall mobility and Hall scattering factor are in good agreement with experimental results. In addition, predicted values of the Hall scattering factor for various temperatures and doping concentrations are given.