Simultaneous Observation of Tungsten Spectra of W0 to W46+ Ions in Visible, VUV and EUV Wavelength Ranges in the Large Helical Device

Spectroscopic studies for emissions released from tungsten ions have been conducted in the Large Helical Device (LHD) for contribution to the tungsten transport study in tungsten divertor fusion devices and for expansion of the experimental database of tungsten line emissions. Tungsten ions are distributed in the LHD plasma by injecting a pellet consisting of a small piece of tungsten metal wire enclosed by a carbon tube. Line emissions from W0, W5+, W6+, W24+–W28+, W37+, W38+, and W41+–W46+ are observed simultaneously in the visible (3200–3550 Å), vacuum ultraviolet (250–1050 Å), and extreme ultraviolet (5–300 Å) wavelength ranges and the wavelengths are summarized. Temporal evolutions of line emissions from these charge states are compared for comprehensive understanding of tungsten impurity behavior in a single discharge. The charge distribution of tungsten ions strongly depends on the electron temperature. Measurements of emissions from W10+ to W20+ are still insufficient, which is addressed as a future task.

CARBON TUBE-BASED NANOTRANSISTORS

В статье рассмотрены нанотранзисторы и основные свойства нанотрубок. Представлен обзор CNTFET транзисторов и основные особенности технологии их изготовления. Полевые транзисторы из углеродных нанотрубок (CNTFET) являются перспективными наноразмерными устройствами для реализации высокопроизводительных схем с очень плотной и низкой мощностью. Проводящий канал CNTFET представляет собой углеродную нанотрубку. The article deals with nanotransistors and the main properties of nanotubes. An overview of CNTFET transistors and the main features of their manufacturing technology is presented. Carbon nanotube field effect transistors (CNTFETs) are promising nanoscale devices for implementing high-performance circuits with very dense and low power. The CNTFET conducting channel is a carbon nanotube.