Design and fabrication of wideband chirped tilted fiber Bragg gratings. (April 2022)

• Record Type: Journal Article
• Authors: Zhao, Xiaofan; Tian, Xin; Wang, Meng; Li, Hongye; Rao, Binyu; Wang, Zefeng
• Is Part Of: Optics & laser technology. Volume 148(2022)
• Publication Date: 2022-04
• Subjects: Chirp and tilted fiber Bragg gratings -- stimulated Raman scattering -- Wideband gratings -- High power fiber lasers; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107790
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: A novel and effective inscription method for wide-band CTFBGs. Effective suppression for SRS in a 5-kW level MOPA fiber laser. Applying of wide-band CTFBG a MOPA laser could provide better SRS suppression. Abstract: Chirped and tilted fiber Bragg gratings (CTFBGs) have been proved to be effective components for Raman suppression in fiber lasers. However, research shows that the rejection bandwidth of CTFBGs is a great limitation for Raman suppression effect, especially at high power level. In this paper, a simple tandem inscription method for achieving wideband CTFBGs (WB-CTFBGs), to the best of our knowledge, is proposed and experimentally validated for the first time. The influence of several key factors including tilt angle, grating period, and chirp rate of phase mask, on the transmission spectrum is studied in detail by simulation. According to the simulation results, a WB-CTFBG is designed and fabricated. The Raman suppression effect in a 5 kW level master-oscillator-power-amplification (MOPA) fiber laser is compared with that of normal CTFBGs. The validity of the proposed inscription technique has been demonstrated by the better Raman suppression effect. This work provides a simple and effective method for fabrication of WB-CTFBGs, which is significant for Raman suppression in high-power fiber laser systems.