Highly Stable Passively Q-Switched Erbium-Doped All-Fiber Laser Based on Niobium Diselenide Saturable Absorber.

Ping Hu,Hongkun Nie,Jiajia Mao,Ruihua Wang,Jingliang He,Baitao Zhang,Tao Li,Kejian Yang

doi:10.3390/molecules26144303

Abstract

A saturable absorber (SA) based on niobium diselenide (NbSe2), which is a layered transition metal dichalcogenide (TMD) in the VB group, is fabricated by the optically driven deposition method, and the related nonlinear optical properties are characterized. The modulation depth, saturable intensity, and nonsaturable loss of the as-prepared NbSe2 nanosheet-based SA are measured to be 16.2%, 0.76 MW/cm2, and 14%, respectively. By using the as-fabricated NbSe2 SA, a highly stable, passively Q-switched, erbium-doped, all-fiber laser is realized. The obtained shortest pulse width is 1.49 μs, with a pulse energy of 48.33 nJ at a center wavelength of 1560.38 nm. As far as we know, this is the shortest pulse duration ever obtained by an NbSe2 SA in a Q-switched fiber laser.

Highlights

Short-pulsed, all-fiber lasers have been widely used in various fields such as material processing, medical diagnosis, industrial processing, light detection, and ranging (LIDAR, LADER), optical fiber communication, and spectroscopy [1,2,3]
The Q-switching mechanism mainly involves the generation of short pulses, whose pulse duration can reach the order of microseconds, nanoseconds, and even picoseconds, while the repetition frequency can range from several Hz to hundreds of kilohertz [5,6]
Compared with other typical 2D materials, such as graphene and black phosphorous (BP), the band gap of transition metal dichalcogenide (TMD) increases with the decrease in the number of layers [16], which introduces broadband absorption helpful for optical modulation [17]

Summary

Introduction

Short-pulsed, all-fiber lasers have been widely used in various fields such as material processing, medical diagnosis, industrial processing, light detection, and ranging (LIDAR, LADER), optical fiber communication, and spectroscopy [1,2,3]. Exploring suitable materials with excellent nonlinear optical response properties is still the key to the development of high-performance pulsed fiber lasers.

Results

Conclusion