摘要
采用折射率匹配耦合法，提出了一种偏振可调的单偏振单模太赫兹光纤。通过在纤芯设计非对称微结构来实现芯模z、y偏振模式的分裂；在包层空气孔中填充折射率匹配液来引入缺陷模式，通过调整液体折射率来分别实现它与芯模z、Y偏振模式的匹配。结果表明，当液体折射率为1．288时，z偏振模式匹配。当入射光频率大于O．73 THz时，偏振损耗比大于100，光纤以Y偏振模式运转；当入射光频率为1 THz时，偏振损耗比达到最大值1020。当液体折射率为1．338时，Y偏振模式匹配。当入射光频率在0．87-0．93 THz时，偏振损耗比大于100，光纤以单偏振模式运转；当入射光频率为O．9 THz时，偏振损耗比达到最大值118。该设计实现了光纤单偏振运转模式的切换，具有宽带、可调、易于实现的特点。
A terahertz single-polarization single-mode （SPSM） fiber with tunable polarization is proposed based on the index-matching coupling method. The asymmetric microstructure is designed in fiber core to split the x and y polarized core modes. The index matching liquid is filled into the air-hole of the fiber cladding, so that the x or y polarized core modes match the defect mode. The matching switch between the two polarized modes is realized by changing the refraction index of filled liquid. The results show that the x polarized mode matches when the refractive index of the liquid is 1. 288. When the frequency of the incident light is higher than 0.73 THz, the polarization loss ratio of the fiber is bigger than 100, and the optical fiber operates in y-polarization mode. At the frequency of 1 THz, the polarization loss ratio reaches the maximum of 1020. The y polarized mode matches when the refractive index of the liquid is 1. 338. From 0.87 THz to 0.93 THz, the polarization loss ratio of the fiber is bigger than 100, and the optical fiber operates in x-polarization mode. At the frequency of 0. 9 THz, the polarization loss ratio reaches the maximum of 118. This design has realized the switch of the single fiber polarization operation mode, and has features such as broadband, tunable and easy to fabricate.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2016年第9期32-38,共7页
Chinese Journal of Lasers
基金
国家973计划(2014CB339800)
国家自然科学基金(61171027)
高等学校博士学科点专项科研基金(20131201120004)
天津市科技计划项目(13RCGFGX01127)
关键词
光纤光学
光子晶体光纤
单偏振单模光纤
折射率匹配耦合法
fiber optics
photonic crystal fiber
single-polarization single mode fiber
indemmatching couplingmethod
