High Power and Large-Energy Pulse Generation in an Erbium-Doped Fiber Laser by a Ferromagnetic Insulator-Cr2Si2Te6 Saturable Absorber

Abstract

Large-energy mode-locked fiber lasers are extensively studied due to their indispensable use in various fields and applications. Recently, ferromagnetic insulators have attracted tremendous research interest in ultra-fast photonics because of their unique ferromagnetic properties and typical layered structure. In our work, Cr2Si2Te6 nanosheets are prepared and utilized as a saturable absorber (SA) in a large-energy mode-locked erbium-doped fiber (EDF) laser. With a total cavity length of 240 m, a stable mode-locked operation characterized by maximum pulse energy as high as 244.76 nJ with a repetition rate of 847.64 kHz is achieved. When the cavity length is extended to 390 m, the output maximum pulse energy is successfully scaled up to 325.50 nJ. To our knowledge, this is the largest pulse energy and highest output power level to be achieved in mode-locked fiber lasers by two-dimensional (2D) material saturable absorbers (SAs) so far. This work not only makes a forward step to the investigation of the generation of large-energy pulses in mode-locked fiber lasers but also fully proves that the ferromagnetic insulator-Cr2Si2Te6 possesses an excellent nonlinear absorption property, antioxidant capacity in ambient conditions, as well as outstanding thermal stability, which enriches our insight into 2D materials.

Passively Q-Switched Er-Doped Fiber Laser Based on Bentonite Clay (Al2H2O6Si) Saturable Absorber

“…Several types of SAs are commonly used in fiber lasers, and a few of them are semiconductor saturable-absorber mirrors (SESAMs) [17], graphene [18], carbon nanotube [19], topological insulators [20], transition metal dichalcogenides [21], oxide-based thin-films [22,23], black-phosphorus [24] and quantum-dots [25]. Typically, these SAs materials lead toward higher absorption at lower optical intensities and become transparent at relatively higher intensities making these materials suitable for the generation of ultrashort pulses of light.…”

Low-Threshold, Multiple High-Order Harmonics Fiber Laser Employing Cr2Si2Te6 Saturable Absorber

“…Cr 2 Si 2 Te 6 , a new layered material belonging to the hexatellurosilicate family [ 40 ], has received a lot of attention in the fields of sensors [ 41 , 42 ] and optical devices [ 43 , 44 ]. The atomic layers of Cr 2 Si 2 Te 6 are bound together by weak van der Waals forces, which also means that multilayered or few-layer 2D nanosheets can be obtained from their bulk-phase materials, by the liquid-phase exfoliation (LPE) method [ 45 ].…”