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81.
PLZT非晶薄膜光学性质研究 总被引:1,自引:7,他引:1
用溶胶-凝胶技术制备了化学组分为5/50/50的PLZT非晶薄膜。测试其200 ̄800nm波长范围的光学透射谱,和200 ̄670nm波长范围的椭偏光谱。得到了PLZT(5/50/50)非晶薄膜膜厚和光学常数谱(折射率n谱和消光系数κ谱),并与组分为9/65/35的PLZT非晶薄膜的吸收边和折射率进行了比较。 相似文献
82.
模拟退火法在椭偏光谱数值反演中的应用 总被引:3,自引:0,他引:3
将模拟退火(SA)法应用于椭偏光谱数值反演,以达到同时得到介质薄膜的厚度和光学常数谱,并对SA算法作了说明和改进,作为应用实例,计算了Si衬底上的SiO2薄膜和Ba0.9Sr0.1TiO3(BST)铁电薄膜的膜厚及光学常数谱,同时讨论了椭扁参数φ和△随膜厚及折射率变化的灵敏度。 相似文献
83.
A.N. Al-Omari G.P. Carey S. Hallstein J.P. Watson G. Dang K.L. Lear 《Photonics Technology Letters, IEEE》2006,18(11):1225-1227
Increasing copper plated heatsink radii from 0 to 4 /spl mu/m greater than the mesa in vertical-cavity surface-emitting lasers (VCSELs) reduced the measured thermal resistance for a range of device sizes to values 50% lower than previously reported over a range of device sizes. For a 9-/spl mu/m diameter oxide aperture, the larger heatsink increases output power and bandwidth by 131% and 40%, respectively. The lasers exhibit a 3-dB modulation frequency bandwidth up to 9.8 GHz at 10.5 kA/cm/sup 2/. The functional dependence of thermal resistance on oxide aperture diameter indicates the importance of lateral heat flow to mesa sidewalls. 相似文献
84.
研究了基于FT245RL和FPGA的USB接口设计方法,介绍了USB通信芯片FT245RL的工作原理及使用方法,设计了FT245RL与FPGA之间硬件电路的连接,给出了FPGA中VHDL的语言描述方法,并介绍了PC机软件的设计方法。实验结果表明,该通信方式数据传输快速稳定,可靠性高。 相似文献
85.
随着我国经济的发展,人们生活水平的提高,居民和各行各业对供电的需求和依赖程度越来越高,传统的供电方式已不能满足用户对供电的要求,这就要采取配电系统自动化运行方式,来保证供电的质量,满足用户的不同要求。 相似文献
86.
Dongfeng Dang Manjun Xiao Pei Zhou Junwei Shi Qiang Tao Hua Tan Yafei Wang Xichang Bao Yu Liu Ergang Wang Renqiang Yang Weiguo Zhu 《Organic Electronics》2014,15(11):2876-2884
A class of low band-gap two-dimensional conjugated polymers of PBDTT-FQ, PBDTT-TQ, PBDTT-BTQ and PBDTT-TTQ was designed and synthesized, which contains the same di(alkylthiophene)-substituted benzo[1,2-b:4,5-b′]dithiophene (BDTT) and 6,7-difluoroquinoxaline (Q) units, as well as various conjugated spacers of furan, thiophene, bithiophene and thieno[3,2-b]thiophene in the main chain. Significant effect of the varied spacers between the BDTT and Q units on the thermal, optical, electrochemical and photovoltaic properties was investigated and observed for these two-dimensional copolymers in the polymer solar cells. The maximum power conversion efficiency of 5.9% with a short circuit current of 13.7 mA/cm2 and a fill factor of 0.56 was obtained for the PBDTT-TQ with thiophene spacer in the bulk hetero-junction PSCs using [6,6]-phenyl-C71-butyric acid methyl ester as acceptor. 相似文献
87.
Flexible Transparent Reduced Graphene Oxide Sensor Coupled with Organic Dye Molecules for Rapid Dual‐Mode Ammonia Gas Detection 下载免费PDF全文
Le Thai Duy Tran Quang Trung Vinh Quang Dang Byeong‐Ung Hwang Saqib Siddiqui Il‐Yung Son Seung Kyun Yoon Dong June Chung Nae‐Eung Lee 《Advanced functional materials》2016,26(24):4329-4338
Flexible chemical sensors utilizing chemically sensitive nanomaterials are of great interest for wearable sensing applications. However, obtaining high performance flexible chemical sensors with high sensitivity, fast response, transparency, stability, and workability at ambient conditions is still challenging. Herein, a newly designed flexible and transparent chemical sensor of reduced graphene oxide (R‐GO) coupled with organic dye molecules (bromophenol blue) is introduced. This device has promising properties such as high mechanical flexibility (>5000 bending cycles with a bending radius of 0.95 cm) and optical transparency (>60% in the visible region). Furthermore, stacking the water‐trapping dye layer on R‐GO enables a higher response as well as workability in a large relative humidity range (up to 80%), and dual‐mode detection capabilities of colorimetric and electrical sensing for NH3 gas (5–40 ppm). These advantageous attributes of the flexible and transparent R‐GO sensor coupled with organic dye molecules provide great potential for real‐time monitoring of toxic gas/vapor in future practical chemical sensing at room conditions in wearable electronics. 相似文献
88.
Ultrabroadband Optical Superchirality in a 3D Stacked‐Patch Plasmonic Metamaterial Designed by Two‐Step Glancing Angle Deposition 下载免费PDF全文
Yidong Hou Ho Ming Leung Che Ting Chan Jinglei Du Helen Lai‐Wai Chan Dang Yuan Lei 《Advanced functional materials》2016,26(43):7807-7816
Low‐cost and large‐scale fabrication of 3D chiral metamaterials is highly desired for potential applications such as nanophotonics devices and chiral biosensors. One of the promising fabrication methods is to use glancing angle deposition (GLAD) of metal on self‐assembled dielectric microsphere array. However, structural handedness varies locally due to long‐range disorder of the array and therefore large‐scale realization of the same handedness is impossible. Here, using symmetry considerations a two‐step GLAD process is proposed to eliminate this longstanding problem. In the proposed scheme, the unavoidable long‐range disorder gives rise to microscale domains of the same handedness but of slightly different structural geometries and ultimately contributes to a broad‐band response. Experimentally, a record‐breaking superchiral response of circular dichroism signal of ≈11° is demonstrated and an average polarization rotation angle of 27° in the visible region on ≈1 cm2 sample is observed. Computer‐aided geometric reconstruction with experimental parameters unambiguously reveal the presence of strong structural anisotropy and chirality in the prepared stacked‐patch plasmonic chiral metamaterial; microscopic spectral analyses combined with full‐wave electromagnetic simulations coherently provide deeper insights into the measured circular dichroism and optical activity. The observed chiroptical response can also be flexibly controlled by adjusting the deposition parameters for various potential applications. 相似文献
89.
针对新疆油田夏盐11井区层内、层间非均质性强,产量持续下降,注水开发后油藏剩余油分布规律不清楚,持续稳产能力较差的问题,利用数值模拟、油藏工程方法及动态监测资料开展了非均质性强油藏不同类型剩余油分布规律研究,明确了下步挖潜对策。研究结果表明:夏盐11井区剩余油挖潜潜力区可分为3种,Ⅰ类为注采井网不完善控制型剩余油,剩余油饱和度高,平均大于45%,油层厚度不小于4.5 m,主要发育水下分流河道,挖潜对策为储层改造提高低渗区域的物性;Ⅱ类为井间滞留型剩余油,剩余油饱和度较高,平均为20%~45%,油层厚度为3.0~4.5 m,主要发育河口坝,挖潜对策为油水井补孔、完善注采井网;Ⅲ类为水淹程度较高型剩余油,剩余油饱和度较低,平均小于20%,油层厚度不超过2 m,剩余油分布零散,挖潜对策为老井补孔和水井分注,同时进行注水井调剖,对低产井进行重复压裂、补孔。该研究可为同类型非均质性油藏开发提供参考。 相似文献
90.