This paper studies the generation of the dispersive wave (DW) in the normal dispersion regimes of the birefringent photonic crystal fiber (BPCF) fabricated in this work. The remarkable blue-shifted radiation is found ...This paper studies the generation of the dispersive wave (DW) in the normal dispersion regimes of the birefringent photonic crystal fiber (BPCF) fabricated in this work. The remarkable blue-shifted radiation is found to be generated when 30 fs pulses are input in the normal dispersion regime of the BPCF for the first time. The characteristics of the blue-shifted DW strongly depend on the polarization of the input pulse. As a result, two peaks appear in the blue-shifted region of the spectrum when the input pulses polarize along the slow axis of the BPCF. With the increase of the center wavelength of the initial input pulse, the difference between the wavelengths of the two peaks widens. The peak location in the spectrum can be explained by the phase matching condition between the DW and the input pulse. In addition, when the input polarization is set to an angle of 45° with respect to the principal axes of the BPCF, the cross-phase modulation and coherent coupling between two orthogonally polarized modes would result in pulse trapping in the BPCF. Accordingly, the DW shift toward short wavelength is restrained. The DW generation in the normal-dispersion regimes of BPCF can be controlled by the phase matching condition and polarization of the input pulse.展开更多
提出了1种基于高双折射光子晶体光纤和无限脉冲响应(IIR)的可调谐可重构微波光子滤波器(MPF).向高双折射光子晶体光纤(HB-PCF)的1个大空气孔中填充温敏液体,调节温度,改变HB-PCF的双折射,使激光器产生不同波长间隔的激光,从而使滤波器...提出了1种基于高双折射光子晶体光纤和无限脉冲响应(IIR)的可调谐可重构微波光子滤波器(MPF).向高双折射光子晶体光纤(HB-PCF)的1个大空气孔中填充温敏液体,调节温度,改变HB-PCF的双折射,使激光器产生不同波长间隔的激光,从而使滤波器具有不同的自由频谱范围(FSR),实现了滤波器的连续可调谐.当温度的变化范围为20-80℃时,仿真测得,FSR的变化范围为12.145-23.277 GHz.在有限脉冲响应(FIR)滤波器中引入电反馈,构成IIR滤波器,使得MPF的3 d B带宽减小,主旁瓣抑制比(MSSR)增加,其通带特性得到了改善.通过调节射频信号放大器的增益,可以改变滤波器的频率响应形状,实现滤波器的可重构特性.展开更多
提出并通过仿真验证了1种基于高双折射光子晶体光纤(HB-PCF)与光栅对的微波光子滤波器.以多波长光纤激光器作光源,通过改变填充温敏液体的HB-PCF周围温度,使HB-PCF具有不同的双折射.随着HB-PCF双折射率的连续变化,激光器输出了不同波长...提出并通过仿真验证了1种基于高双折射光子晶体光纤(HB-PCF)与光栅对的微波光子滤波器.以多波长光纤激光器作光源,通过改变填充温敏液体的HB-PCF周围温度,使HB-PCF具有不同的双折射.随着HB-PCF双折射率的连续变化,激光器输出了不同波长间隔的激光,使微波光子滤波器具有不同的自由频谱范围,当温度的变化范围为20-80℃时,FSR的变化范围为18.62-25.98 GHz,从而实现了连续可调谐.通过引入单模光纤与光栅对级联,改变光栅对的反射系数和掺铒光纤的增益,使滤波器的主旁瓣抑制比提高到33 d B,Q值可达到1 553,有效地提高了滤波器的频率选择性.展开更多
基金supported in part by the National Natural Science Founda-tion of China (Grant No. 10874145)Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20091333110010)+1 种基金the Nature Science Foundation of Hebei Province (Grant No. F2009000481)the China Postdoctoral Science Foundation (Grant Nos. 20080440014 and 200902046)
文摘This paper studies the generation of the dispersive wave (DW) in the normal dispersion regimes of the birefringent photonic crystal fiber (BPCF) fabricated in this work. The remarkable blue-shifted radiation is found to be generated when 30 fs pulses are input in the normal dispersion regime of the BPCF for the first time. The characteristics of the blue-shifted DW strongly depend on the polarization of the input pulse. As a result, two peaks appear in the blue-shifted region of the spectrum when the input pulses polarize along the slow axis of the BPCF. With the increase of the center wavelength of the initial input pulse, the difference between the wavelengths of the two peaks widens. The peak location in the spectrum can be explained by the phase matching condition between the DW and the input pulse. In addition, when the input polarization is set to an angle of 45° with respect to the principal axes of the BPCF, the cross-phase modulation and coherent coupling between two orthogonally polarized modes would result in pulse trapping in the BPCF. Accordingly, the DW shift toward short wavelength is restrained. The DW generation in the normal-dispersion regimes of BPCF can be controlled by the phase matching condition and polarization of the input pulse.
文摘提出了1种基于高双折射光子晶体光纤和无限脉冲响应(IIR)的可调谐可重构微波光子滤波器(MPF).向高双折射光子晶体光纤(HB-PCF)的1个大空气孔中填充温敏液体,调节温度,改变HB-PCF的双折射,使激光器产生不同波长间隔的激光,从而使滤波器具有不同的自由频谱范围(FSR),实现了滤波器的连续可调谐.当温度的变化范围为20-80℃时,仿真测得,FSR的变化范围为12.145-23.277 GHz.在有限脉冲响应(FIR)滤波器中引入电反馈,构成IIR滤波器,使得MPF的3 d B带宽减小,主旁瓣抑制比(MSSR)增加,其通带特性得到了改善.通过调节射频信号放大器的增益,可以改变滤波器的频率响应形状,实现滤波器的可重构特性.
文摘提出并通过仿真验证了1种基于高双折射光子晶体光纤(HB-PCF)与光栅对的微波光子滤波器.以多波长光纤激光器作光源,通过改变填充温敏液体的HB-PCF周围温度,使HB-PCF具有不同的双折射.随着HB-PCF双折射率的连续变化,激光器输出了不同波长间隔的激光,使微波光子滤波器具有不同的自由频谱范围,当温度的变化范围为20-80℃时,FSR的变化范围为18.62-25.98 GHz,从而实现了连续可调谐.通过引入单模光纤与光栅对级联,改变光栅对的反射系数和掺铒光纤的增益,使滤波器的主旁瓣抑制比提高到33 d B,Q值可达到1 553,有效地提高了滤波器的频率选择性.