A Passively Q-Switched Holmium-Doped Fiber Laser with Graphene Oxide at 2058 nm

Abstract

This study reports a Q-switching-based, 2058-nm holmium (Ho) fiber laser incorporating a saturable absorber (SA) based on graphene oxide (GO). The SA was prepared with a side-polished fiber, while GO particles were deposited onto the fiber-polished surface to realize an all-fiber SA. A continuous-wave thulium-doped all-fiber laser, which was configured with a master-oscillator power-amplifier (MOPA) structure, was constructed as a pumping source. By inserting the fabricated SA into an all-fiber ring resonator based on 1-m length of Ho-doped fiber, Q-switched pulses could readily be obtained at a wavelength of 2058 nm. The pulse width was observed to vary from 2.01 to 1.56 μs as the pump power was adjusted from ~759 to 1072 mW, while the repetition rate was tunable from 45.56 to 56.12 kHz. The maximum values of average optical power and pulse energy were measured as ~11.61 mW and 207.05 nJ, respectively, at a ~1072 mW pump power.

Passively Modelocked All-PM Thulium-Doped Fiber Laser at 2.07μm

“…Despite this natural predisposition to use HDF as a medium gain above 2 m there are other reasons of a practical nature to prefer TDFs. One of them is the easier availability of pumping sources for TDFs, which can be pumped at 0.79 or 1.56 m [9], while HDFs require fewer available pumping sources at 1.1 or 1.9 μm [12]. Another reason is the strong overlap between the emission and absorption bands in HDFs, which promotes re-absorption [9].…”

Broadband Metallic Carbon Nanotube Saturable Absorber for Ultrashort Pulse Generation in the 1500–2100 nm Spectral Range

“…Since then, the family of nanomaterials exhibiting nonlinear optical absorption with ultrashort recovery times has expanded quickly. A pioneering two-dimensional material, graphene [8,9], was soon joined by graphene oxide [10], black phosphorus [11,12], transition metal monochalcogenides [13], transition metal dichalcogenides such as molybdenum disulfide [14,15] or tungsten disulfide [16,17], and topological insulators including bismuth telluride [18] and antimony telluride [19]. More recently, MXenes [20], bismuthene [21], and antimonene [22] were also found to show the desired nonlinear optical properties.…”