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An ion cyclotron range of frequencies (ICRF) system with power up to 6.0MW and a lower hybrid current drive (LHCD) system up to 4MW have been applied for heating and current drive experiments in Experimental Advanced Superconducting Tokomak (EAST). Significant progress has been made with ICRF heating and LHCD for realizing the H-mode plasma operation in EAST. During 2010 and 2012 experimental campaigns, ICRF heating experiments were carried out at the fixed frequency of 27MHz, achieving effective ions and electrons heating with the H minority heating (H-MH) mode. The H-MH mode produced good plasma performance, and realized H-mode using ICRF power alone in 2012. In 2010, H-modes were generated and sustained by LHCD alone, where lithium coating and gas puffing near the mouth of the LH launcher were applied to improve the LHCD power coupling and penetration into the core plasmas of H-modes. In 2012, the combination of LHCD and ICRH power extended the H-mode duration up to over 30 s. H-modes with various types of edge localized modes (ELMs) have been achieved with HIPB98(y, 2) ranging from 0.7 to over unity. A brief overview of LHCD and ICRF Heating experiment and their application in achieving H-mode operation during these two campaigns will be presented. [ABSTRACT FROM AUTHOR]

Abstract: Sputtering plasma state intensely depends on the variation of deposition parameters. It results in different properties of sputtering thin films finally. Here, we use reactive sputter gas controller (Lambda sensor) to control oxygen partial pressure in the process, so that we can achieve the same sputtering plasma state during the process of sputtering aluminium doped zinc oxide (AZO) thin films. At the same time, we use the intensity of Zn (470nm) and O (780nm) plasma emission peak signal to estimate the variation of the sputtering plasma state at different Lambda sensor value. In this experiment, AZO thin films are also prepared by pulse reactive magnetron sputtering on CORNING Eagle 2000 glasses. High purity metallic Zn-Al (Al 2wt. %) alloy target and oxygen are used as source materials. The microstructure and surface morphology, optical and electrical properties of AZO films with various substrate temperatures are investigated in detail. Sputtering plasma state affects the properties of sputtering AZO thin films. At the optimized plasma state and substrate temperate, we get the AZO thin films with more than 85% average transmissions in the visible and near-infrared range and the resistivity less than 8.5×10-4 Ωcm. [Copyright &y& Elsevier]

Using a 2 MW 2.45 GHz lower hybrid wave (LHW) system installed in experimental advanced superconducting tokamak, we have systematically carried out LHW-plasma coupling and lower hybrid current drive experiments in both divertor (double null and lower single null) and limiter plasma configuration with plasma current (Ip) ∼ 250 kA and central line averaged density (ne) ∼ 1.0-1.3 × 1019 m-3 recently. Results show that the reflection coefficient (RC) first is flat up to some distance between plasma and LHW grill, and then increases with the distance. Studies indicate that with the same plasma parameters, the best coupling is obtained in the limiter case (with plasma leaning on the inner wall), followed by the lower single null, and the one with the worst coupling is the double null configuration, explained by different magnetic connection length. The RCs in the different poloidal rows show that they have different coupling characteristics, possibly due to local magnetic connection length. Current drive efficiency has been investigated by a least squares fit with N//peak=2.1, where N//peak is the peak value of parallel refractive index of the launched wave. Results show that there is no obvious difference in the current drive efficiency between double null and lower single null cases, whereas the efficiency is somewhat small in the limiter configuration. This is in agreement with the ray tracing/Fokker-Planck code simulation by LUKE/C3PO and can be interpreted by the power spectrum up-shift factor in different plasma configurations. A transformer recharge is realized with ∼0.8 MW LHW power and the energy conversion efficiency from LHW to poloidal field energy is about 2%. [ABSTRACT FROM AUTHOR]

Extreme ultraviolet (EUV) radiation with wavelengths of 11-14 nm is seen as the most promising candidate for a new lithographic technology. Compared with synchrotron radiation sources and laser-produced plasmas, gas discharge-produced plasma sources for EUV radiation are expected to offer lower cost of ownership. Using xenon, a broadband emission in the investigated wavelength range from 10 to 17 nm is observed. Very short current pulses, having a fast rise time of 85- or 140-ns duration and 23-kA amplitude, were applied across the xenon-filled Z-pinch capillary (3-mm diameter and 5-mm length) to produce EUV radiation. An EUV radiation from the Z-pinch plasma was characterized, which is based on the temporal behavior of EUV intensity and the pinhole images. Two maximum EUV radiations occur, which are sensitive to the xenon flow rate and the discharge current. The first radiation is relatively of short duration, while the second radiation lasts as long as the first period of the current flows. The EUV source size due to the first radiation is approximately 300 µm, i.e., half of the one due to the second radiation. [ABSTRACT FROM AUTHOR]