利用倾斜光纤光栅的可开关双波长光纤激光器  

Switchable Dual-Wavelength Erbium-Doped Fiber Laser with a Tilted Fiber Bragg Grating

作　　者：徐玲玲[1] 金龙[1] 开桂云[1] 张键[1] 刘艳格[1] 袁树忠[1] 董孝义[1] 

机构地区：[1]南开大学现代光学研究所,天津300071

出　　处：《光学学报》2007年第9期1658-1662,共5页Acta Optica Sinica

基　　金：国家973计划(2003CB314906)资助课题

摘　　要：报导了一种在四波混频作用下利用倾斜光纤布拉格光栅进行波长选择的可开关双波长掺铒光纤激光器。通过将倾斜光纤光栅与单模光纤进行横向错位焊接,使光栅的反向LP01和LP11两个模式具有相近的有效反射率,从而可以用来进行激光器的双波长选择。接入腔内的一段高非线性光子晶体光纤引入的四波混频效应克服了模式竞争,使得双波长激光在室温下稳定振荡。腔内起偏器和偏振控制器的联合作用可产生依赖于波长的损耗,以补偿光纤光栅两反射峰峰值的大小差异。基于以上原理,通过调节腔内的偏振态,该激光器实现了室温下稳定的双波长输出,也实现了在两波长之间的转换。两波长激光均有超过45 dB的信噪比,最大的功率波动为0.8A four-wave mixing （FWM） assisted dual-wavelength erbium-doped fiber laser with a tilted fiber Bragg grating （TFBG） for wavelength switch is reported. The transverse-offset-spliced tilted fiber grating on single-mode fiber ensures that the two effective reflectivities of the reverse LP01 mode and LP11 mode are close enough to realize the dual-wavelength switch for laser. FWM process induced by high-nonlinearity photonic crystal fiber （HNL-PCF） avoids mode competition and ensures stable dual-wavelength oscillation at room temperature. The conjunction of a polarization controller （PC） and a polarizer introduces wavelength-dependent cavity loss and balances the reflectivity difference of the two wavelengths. By adjusting the intracavity polarization state, the proposed laser can operate in stable dual-wavelength or switch between two wavelengths at room temperature. The two lasing lines have a high signal-noise-ratio （OSNR） more than 45 dB and a maximum power fluctuation of 0.8 dB.

关 键 词：激光器 掺铒光纤激光器 四波混频 倾斜光纤布拉格光栅 光子晶体光纤 

分 类 号：TN248[电子电信—物理电子学]