Experimental study of MMI structures in a switchable continuous-wave thulium-doped all-fiber laser. (September 2022)

• Record Type: Journal Article
• Authors: Camarillo-Avilés, A.; Hernández-Arriaga, M.V.; López-Estopier, R.; Bello-Jiménez, M.; Pottiez, O.; Durán-Sánchez, M.; Ibarra-Escamilla, B.; Andrés, M.V.
• Is Part Of: Optics & laser technology. Volume 153(2022)
• Publication Date: 2022-09
• Subjects: Multimodal interference -- Thulium doped fiber -- Multi-wavelength emission -- Coreless optical fiber; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2022.108231
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: Switchable multiwavelength laser emission is reported in an all-fiber system. CW emissions were obtained in a tapered and a non-tapered MMI filters. The laser supports a single-, dual-, and triple-emission above 2 mm. Maximum output power was measured at 13.35 mW with a linewidth of ∼ 50 pm. Our scheme is highly reproducible and preserves its robustness. Abstract: Switchable multi-wavelength laser emission from a thulium-doped all-fiber laser is reported by implementing a tapered and a non-tapered multi-modal interference (MMI) filters. The MMI structure relies on a coreless optical fiber spliced in between two single-mode optical fibers. For the non-tapered case, a minimum insertion loss of 12.60 dB is achieved around the 2-µm region, from which stable generation of commutable dual-wavelength emission at 1986.34 nm and 2017.38 nm is obtained. On the other hand, the tapered MMI structure performs a minimum insertion loss of 8.74 dB at the 2-µm region, allowing a stable triple-wavelength emission at 1995.4 nm, 2013.3 nm, and 2038.3 nm. In addition, commutable dual-wavelength emission was also obtained at 1997.9 nm and 2032.1 nm. The generated laser lines perform bandwidths of around 50 pm, low peak spectral power fluctuations and signal-to-noise ratio of 50 dB.