Dust-plasma interactions play vital roles in numerous observed phenomena in the space environment, their scope in the industrial laboratory has grown rapidly in recent times to include such diverse areas as materials ...Dust-plasma interactions play vital roles in numerous observed phenomena in the space environment, their scope in the industrial laboratory has grown rapidly in recent times to include such diverse areas as materials processing, microelectronics, lighting and nuclear fusion. The etching processes of Si wafer has been studied using Ultra low frequency RF plasma (ULFP) at (1 KHz) by two different techniques namely: ion etching using inert gas only (e.g., argon gas), and ion chemical etching using an active gas (beside the inert gas) such as oxygen. In the case of large dust particle, the dust might act as a floating body in the plasma collecting equal fluxes of electrons and ions. The velocity of the ions flux out from the mesh (cathode) and cause ion sputtering for the sample (Si-Wafer) measured, moreover the rate coefficient for collection of electrons and ions by dust (K) is calculated here, the presence of dust, however, may itself cause loss process. As the plasma density increases, the etching rate increases and the volumetric rate of loss of electron and ions due to dust particle increases (K). A comparison between the volumetric rate of loss (K) due to ion chemical etching (75% Ar/25% O2) and ion etching (Pure Ar) has been carried out.展开更多
提出了一种新颖的超低损耗G.654光纤结构设计,光纤从中心到外周依次包括纤芯、渐变层、内包层、平台层、凹陷包层、过渡层和外包层。渐变层的设计,可显著减小或消除由于芯层和内包层之间物理性能失衡而引起的应力。通过将凹陷移到远离...提出了一种新颖的超低损耗G.654光纤结构设计,光纤从中心到外周依次包括纤芯、渐变层、内包层、平台层、凹陷包层、过渡层和外包层。渐变层的设计,可显著减小或消除由于芯层和内包层之间物理性能失衡而引起的应力。通过将凹陷移到远离芯层的位置,全面优化了光纤设计。在提高大曲率弯曲性能的同时,有效地减小了凹陷对截止波长的影响,从而允许设计更大有效面积的光纤。设计优化的光纤在1 625 nm处的弯曲损耗(R30-100圈)均小于0.05 d B,同时模场直径(MFD)均大于12.0μm,满足G.654.E标准。展开更多
文摘Dust-plasma interactions play vital roles in numerous observed phenomena in the space environment, their scope in the industrial laboratory has grown rapidly in recent times to include such diverse areas as materials processing, microelectronics, lighting and nuclear fusion. The etching processes of Si wafer has been studied using Ultra low frequency RF plasma (ULFP) at (1 KHz) by two different techniques namely: ion etching using inert gas only (e.g., argon gas), and ion chemical etching using an active gas (beside the inert gas) such as oxygen. In the case of large dust particle, the dust might act as a floating body in the plasma collecting equal fluxes of electrons and ions. The velocity of the ions flux out from the mesh (cathode) and cause ion sputtering for the sample (Si-Wafer) measured, moreover the rate coefficient for collection of electrons and ions by dust (K) is calculated here, the presence of dust, however, may itself cause loss process. As the plasma density increases, the etching rate increases and the volumetric rate of loss of electron and ions due to dust particle increases (K). A comparison between the volumetric rate of loss (K) due to ion chemical etching (75% Ar/25% O2) and ion etching (Pure Ar) has been carried out.
文摘提出了一种新颖的超低损耗G.654光纤结构设计,光纤从中心到外周依次包括纤芯、渐变层、内包层、平台层、凹陷包层、过渡层和外包层。渐变层的设计,可显著减小或消除由于芯层和内包层之间物理性能失衡而引起的应力。通过将凹陷移到远离芯层的位置,全面优化了光纤设计。在提高大曲率弯曲性能的同时,有效地减小了凹陷对截止波长的影响,从而允许设计更大有效面积的光纤。设计优化的光纤在1 625 nm处的弯曲损耗(R30-100圈)均小于0.05 d B,同时模场直径(MFD)均大于12.0μm,满足G.654.E标准。
文摘对长距离传输系统而言,低损耗光纤是不可缺少的传输媒介,目前世界上已经开发出了超低损耗0.1484 dB/km的光纤,刷新了早在1986年创造的0.154 dB/km的记录。这种超低损耗光纤是通过改进纯石英(二氧化硅)纤芯而得到的,其大有效截面积为118μm2,有助于抑制非线性效应。本文也简述了该光纤可能对传输系统的一些影响,传输损耗在宽广的波长范围内(C和L波段)低于0.160 dB/km,这对于EDFA(掺铒光纤放大器)系统是非常有吸引力的;在无中继传输系统中,与传统的Ge-SMF光纤相比,低损耗光纤可使传输距离增大33%,当该超低损耗光纤与后向泵谱分布式喇曼放大器结合使用时,有可能使传输距离增大到400 km.
