Q-switched dual-wavelength fiber laser using a graphene oxide saturable absorber and singlemode–multimode–singlemode fiber structure

Abstract

A Q-switched dual-wavelength fiber laser using a graphene oxide-based saturable absorber to generate the desired output pulses is proposed and demonstrated. The system utilizes a singlemode–multimode–singlemode fiber structure to control the net losses in the cavity so that only two dominant wavelengths are allowed to oscillate. The proposed system is capable of generating an output with a high repetition rate of 27.1 kHz and a narrow pulse width of 4.03 µs. The output pulses also have average output power and pulse energy of up to 0.5 mW and 18.5 nJ, respectively. The 1st harmonic obtained has a high signal-to-noise ratio of 33.2 dB, indicating a highly stable pulse output with minimum mode hopping.

TunableQ-switched erbium-doped fiber laser based on curved multimode fiber and graphene oxide saturable absorber

“…An I D /I G ratio of 0.91 is acquired, which further verifies the presence of GO in the sample [22]. The Raman trace of this sample has been reported in [13].…”

“…The system is built around a conventional erbium-doped fiber laser (EDFL) as the primary gain medium, with an SMS structure providing tunability. The proposed SMS fiber has already been proven able to generate a dual-wavelength output using an SMS fiber sandwiched between two polymers [13], while in this work the SMS fiber is used in freespace as a mechanism to tune the lasing wavelength of a Q-switched laser pulse. A graphene oxide (GO) based saturable absorber (GOSA) is also incorporated into the cavity to provide a Q-switched output in the C-band region.…”

“…Thus, efforts continue in the search for a viable solution to the generation of tunable, multi-wavelength outputs. In this regard, singlemode-multimode-singlemode fiber structures (SMS) have emerged as a highly promising potential candidate that is cost-effective, easy to fabricate, useful and repeatable [12][13][14]. SMS systems are simple to fabricate, requiring only the splicing of two singlemode fibers (SMFs) to a multimode fiber (MMF) and are very low-cost in nature, as well as having greater sensitivity to strain as compared to fiber Bragg gratings (FBGs) [15,16].…”

Responsiveness of temperature using tunable dual-wavelength Q-switched fiber laser

“…Multi-wavelength switchable fiber lasers or dual-wavelength switchable fiber lasers are widely used in laser technology [1], fiber optic sensing [2], optical communication [3] and also in the design of optical division multiplexing mechanism (WDM) [2][3][4][5]. Multi-wavelength mode-locked and Qswitched pulses in fiber lasers have been successfully achieved using both active and passive approaches.…”