排序方式: 共有32条查询结果,搜索用时 15 毫秒
21.
1引言设ΩСR2为一个凸的有界开集,边界为ЭΩ;T为一个正常数.我们考虑如下基于Maxwell模型的二维粘弹性固体介质波传导问题。 相似文献
22.
Device simulation of quasi-two-dimensional perovskite/silicon tandem solar cells towards 30%-efficiency
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Xiao-Ping Xie 《中国物理 B》2022,31(10):108801-108801
Perovskite/silicon (Si) tandem solar cells have been recognized as the next-generation photovoltaic technology with efficiency over 30% and low cost. However, the intrinsic instability of traditional three-dimensional (3D) hybrid perovskite seriously hinders the lifetimes of tandem devices. In this work, the quasi-two-dimensional (2D) (BA)2(MA)n-1PbnI3n+1 (n=1, 2, 3, 4, 5) (where MA denotes methylammonium and BA represents butylammonium), with senior stability and wider bandgap, are first used as an absorber of semitransparent top perovskite solar cells (PSCs) to construct a four-terminal (4T) tandem devices with a bottom Si-heterojunction cell. The device model is established by Silvaco Atlas based on experimental parameters. Simulation results show that in the optimized tandem device, the top cell (n=4) obtains a power conversion efficiency (PCE) of 17.39% and the Si bottom cell shows a PCE of 11.44%, thus an overall PCE of 28.83%. Furthermore, by introducing a 90-nm lithium fluoride (LiF) anti-reflection layer to reduce the surface reflection loss, the current density (Jsc) of the top cell is enhanced from 15.56 mA/cm2 to 17.09 mA/cm2, the corresponding PCE reaches 19.05%, and the tandem PCE increases to 30.58%. Simultaneously, in the cases of n=3, 4, and 5, all the tandem PCEs exceed the limiting theoretical efficiency of Si cells. Therefore, the 4T quasi-2D perovskite/Si devices provide a more cost-effective tandem strategy and long-term stability solutions. 相似文献
23.
24.
25.
All-Optical RZ to NRZ Format Conversion Using Single SOA Assisted by Optical Band-Pass Filter 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We propose a novel all-optical format conversion from the return-to-zero (RZ) to the non-return-to-zero (NRZ) based on single semiconductor optical amplifier (SOA) and optical band-pass filter (OBE). We demonstrate the proof of the principle experiment at 10 Gbps by using the test SOA and OBF converter. The format conversion can be achieved with output extinction ratio of 11.51 dB. The BER is 5.5×10^-9 when the power of NRZ is - 10 dBm. The proposed scheme is robust and potential for applications in optical networks. 相似文献
26.
针对光分组交换网络中光开关插入损耗导致交换跳数受限的问题,基于半导体光放大器四波混频非线性效应,提出了一种两级级联的增益光开关技术思路,可以有效实现光交换后输出信号的增益补偿及形状再生,提高信号质量.利用Opti System仿真平台,优化系统参数,在泵浦光位于信号光中心波长±4 nm范围、泵浦光功率在(3~15)d Bm区间内,增益光交换输出信号通过增益补偿和形状再生相较于一级交换输出信号可实现增益大于25 d B、误码率从10-5提高至10-18、Q因子从4.16提高至8.71的大幅度质量改善.该技术在多跳光分组交换网络中有较大应用前景. 相似文献
27.
本文针对带有随机杨氏模量和荷载的平面线弹性问题,提出了一类随机弱Galerkin有限元方法.先利用Karhunen-Loève展开把随机项参数化,将方程转化为一个确定性问题;再采用弱Galerkin有限元法和k-/p-型方法分别离散空间区域和随机场.在弱Galerkin离散中,用分片s(s≥1)和s+1次多项式逼近单元... 相似文献
28.
29.
高考是一种与速度赛跑的比赛.在高考中,它除了考查我们的常规知识、常规方法与常规思想外,还需要我们去总结一些结论,来加快我们的解题速度.而这就需要我们平时多去探索与研究,不要就题解题,应从题中看到类型,举一反三,从而上升为结论.而此篇论文就是有感于06年江西理科高考选择题第10题,题目如下。 相似文献
30.
蓝绿LED通信被认为是解决水下近距离高速无线数据传输的有效手段。然而由于LED发散角较大,造成通信链路的几何损耗增加,制约了水下LED通信距离的提升。针对这一问题,提出了一种基于全内反射(TIR)透镜压缩水下LED通信阵列光源出射角的方法,将LED通信光源的出射角从130°压缩到7°;利用该光源研制发射样机,在大型水池中搭建测试系统,并对发射机的性能进行测试。结果表明,所设计的通信样机在水下传输距离为16.6 m时,最大可支持23 Mbit/s的传输速率;与未采用TIR透镜时相比,在同等速率条件下,传输距离增加9.3 m。这表明基于TIR透镜二次配光的方法,可有效减小发射机出射角,降低链路损耗,增强通信系统的传输能力。这为提升水下LED通信的传输性能提供了新的技术思路。 相似文献