【摘 要】
：
We investigate the coupling characteristics of photonic crystal fiber composed of two cores with different index profiles. The index curves of the fundamental modes of the two cores can cross at a desired wavelength by choosing appropriate index profiles
【机 构】
：
DepartmentofOpticalEngineering,SchoolofMechanicalEngineering,JiangsuUniversity,Zhenjiang212013,China
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
We investigate the coupling characteristics of photonic crystal fiber composed of two cores with different index profiles. The index curves of the fundamental modes of the two cores can cross at a desired wavelength by choosing appropriate index profiles of the cores. As a result, wavelength-selective coupling is achieved. The designed coupler can be applied as an optical fiber bandstop filter with 26-nm bandwidth.
其他文献
针对几何映射理论不考虑衍射效应,无法得到精确的输出光束,且输出光束存在严重振铃效应的问题,提出一种设计衍射光学元件的新算法。设置一个用于反映衍射效应的参量,通过迭代的方法确定该参量的最佳取值,再用改进的Gerchberg-Saxton(GS)算法对初始相位进行修正,最终得到所需衍射光学元件的相位分布。该算法与传统GS算法相比,能有效抑制散斑和振铃效应,得到均匀性更好的输出光束。
针对生物活细胞的观测，基于预放大离轴光路设计和构建了一套倒置式像面数字全息显微成像系统，该系统的全息图记录平面与物体的像面重合，无需光学衍射传播步骤，简化了再现过程。对于引入到相位像中的畸变，采用简单快速的曲面拟合法予以校正；并利用分辨率板对系统实际分辨率进行测定，该系统可以分辨的最小细节信息为0.87 μm。以老鼠的大脑海马区神经元活细胞为成像物体，实现了其在自然状态下的定量相衬成像，清晰观察到了海马区神经元活细胞的胞体、树突等形态结构，获得了细胞形态的基本参数。结果表明，数字全息术可用于神经元等活体细
An approach to the simultaneous measurement of refractive-index (RI) and temperature changes using optical ring resonators is proposed and theoretically demonstrated. With a liquid-core silica ring resonator as an example, two different-order whispering g
A simple fiber tip sensor for refractive index (RI) measurement based on Fabry–Perot (FP) interference modulated by Fresnel reflection is proposed and demonstrated. The sensor head consists of an etching-induced micro air gap near the tip of a single-mode
To determine whether a potassium dihydrogen phosphate (KDP) surface mitigated by micro-milling would potentially threaten downstream optics, we calculated the light-field modulation based on angular spectrum diffraction theory, and performed a laser damag
采用磷硼共扩散的方法制备了N型高效双面电池,通过优化背场及发射极扩散工艺,研究了扩散工艺曲线对电池电性能参数的影响机理。实验结果表明,降低背场扩散方块电阻可提高电池填充因子,同时造成开路电压(Voc)和短路电流(Isc)降低,需要在背场饱和电流密度(J0BSF)和填充因子(FF)之间找到一个平衡点；降低发射极表面杂质浓度和方块电阻并适当的增加结深,可改善与金属化栅线的接触。正面采用低浓度深结扩散工艺可改善Voc和FF,减少复合,提高Isc,电池效率增加了0.2%,平均效率达到20.41%。
A differential carbon monoxide (CO) concentration sensing device using a self-fabricated spherical mirror (e.g. light-collector) and a multi-pass gas-chamber is presented in this paper. Single-source dual-channel detection method is adopted to suppress th
用自制的单光子计数系统,测定了氩在α粒子激励下的发射光谱.在 300～600 nm范围,认证得到4条 Arl,24条 ArⅡ1条ArⅢ谱线.实验研究了谱线强度随气体压强的变化规律.经初步统计分析,提出在472.8 nm,487.9nm等谱线上实现核泵浦激光振荡的可能性.
基于非微扰量子电动力学的频域理论,研究了原子在不同频率双色激光场中的阈上电离过程。当两个激光场的频率均远低于原子电离势时,阈上电离谱来自大量通道的干涉结果,两个激光场在电离过程中起到相同的作用。随着激光频率的增加,阈上电离谱逐渐呈现多平台结构,不同平台对应电子吸收不同高频光子的过程。当一个激光场的单个光子能量远大于原子电离势时,两个激光场在电离过程中起到不同的作用,高频激光场决定原子的电离概率,低频激光场决定原子阈上电离谱每个平台的宽度,且平台宽度可以很好地用能量守恒公式给出。