A comb fiber filter based on modal interference is proposed and demonstrated in this paper. Here two cascaded uptapers are used to excite the cladding mode, and a core-offset jointing point is used to act as an interf...A comb fiber filter based on modal interference is proposed and demonstrated in this paper. Here two cascaded uptapers are used to excite the cladding mode, and a core-offset jointing point is used to act as an interference component.Experimental results show that this kind of structure possesses a comb filter property in a range of the C-band. The measured extinction ratio is better than 12 dB with an insertion loss of about 11 dB. A switchable multi-wavelength erbium-doped fiber laser based on this novel comb filter is demonstrated. By adjusting the polarization controller, the output laser can be switched among single-, dual-, and three-wavelengths with a side mode suppression ratio of better than 45 dB.展开更多
文摘A comb fiber filter based on modal interference is proposed and demonstrated in this paper. Here two cascaded uptapers are used to excite the cladding mode, and a core-offset jointing point is used to act as an interference component.Experimental results show that this kind of structure possesses a comb filter property in a range of the C-band. The measured extinction ratio is better than 12 dB with an insertion loss of about 11 dB. A switchable multi-wavelength erbium-doped fiber laser based on this novel comb filter is demonstrated. By adjusting the polarization controller, the output laser can be switched among single-, dual-, and three-wavelengths with a side mode suppression ratio of better than 45 dB.