中红外高保偏硫系玻璃双芯光子晶体光纤耦合特性研究

设计了一种中红外硫系玻璃双芯光子晶体光纤,利用多极法和模式耦合基本理论研究了这种光纤的耦合特性.数值模拟发现,空气孔间距Λ = 5.4 μm,空气孔半径为r = 1.35 μm,空气填充率d/Λ = 0.5的光纤,在归一化波长λ/Λ = 2.04 μm处双折射可以达到0.551×10^-2,在归一化波长λ/Λ = 0.93 μm处x偏振方向的耦合长度为145.32 μm,y偏振方向的耦合长 关键词： 双芯光子晶体光纤 硫系玻璃 双折射 耦合长度     

A Kind of Double-Cladding Photonic Crystal Fiber with High Birefringence and Two Zero-Dispersion Wavelengths

A kind of double-cladding photonic crystal fiber （DC-PCF） with high birefringence and two zero-dispersion wavelengths is proposed. It is found that the birefringence of DC-PCF with inner cladding air holes pitch 1.0μm and diameter 0.8μm is 1.001×10-2 in the optical communication band at wavelength 1.55μm by the multipole method. It is demonstrated that two zero dispersion wavelengths can be achieved in the optical communication band between 0.8μm and 1.7μm, and the first zero-dispersion wavelength is in the working wave band of the Ti：sapphire oscillator, which contributes to the frequency conversion of the Ti：sapphire femtosecond laser. PCF with two zero-dispersion wavelengths can make strong power supercontinuum spectral in the near infrared band.     

一道光学计算题被遗漏的另一个临界点

如下是一道有关光学的计算题，出现在“2014河北省名校名师俱乐部高三模拟考试理科综合试卷”中，但只给出了其中一个临界点的解答，笔者认为还有另外一个临界点被遗漏了，今提出来供大家参考。