Stable mode-locked fiber laser based on CVD fabricated graphene saturable absorber

Abstract

A stable mode-locked fiber laser (MLFL) employing multi-layer graphene as saturable absorber (SA) is presented. The multi-layer graphene were grown by chemical vapor deposition (CVD) on Ni close to A-A stacking. Linear absorbance spectrum of multi-layer graphene was observed without absorption peak from 400 to 2000 nm. Optical nonlinearities of different atomic-layers (7-, 11-, 14-, and 21- layers) graphene based SA are investigated and compared. The results found that the thicker 21-layer graphene based SA exhibited a smaller modulation depth (MD) value of 2.93% due to more available density of states in the band structure of multi-layer graphene and favored SA nonlinearity. A stable MLFL of 21-layer graphene based SA showed a pulsewidth of 432.47 fs, a bandwidth of 6.16 nm, and a time-bandwidth product (TBP) of 0.323 at fundamental soliton-like operation. This study demonstrates that the atomic-layer structure of graphene from CVD process may provide a reliable graphene based SA for stable soliton-like pulse formation of the MLFL.

A passively Q-switched Ho:YVO4 Laser at 2.05 μm with Graphene Saturable Absorber

“…The graphene we chose for our experiment was produced by chemical vapor deposition (CVD). Compared with graphene-polymer composites and epitaxial growth on SiC, the graphene produced by CVD has many advantages such as lower defects, a large area and controllable grapheme layers [24]. The dimension of the graphene was 7ˆ7 mm 2 in cross section.…”

“…Sci. 2016, 6, 128 3 of 8 advantages such as lower defects, a large area and controllable grapheme layers [24]. The dimension of the graphene was 7 × 7 mm 2 in cross section.…”

Q-Switched Operation with Carbon-Based Saturable Absorbers in a Nd:YLF Laser

“…While in fiber lasers, multilayer graphene [15] or graphene nanoparticles [16] have been used to produce mode locking in erbium-doped fiber lasers.…”

Mode-locked 2-μm wavelength fiber laser using a graphene-saturable absorber

“…2 Since then, mode-locked lasers have been created using graphene as a saturable absorber at wavelengths in the near IR. [3][4][5][6][7][8][9][10] Theory predicts graphene's performance as a saturable absorber at wavelengths beyond 1.55 μm. 9 Graphene's broadband performance has been shown by a few groups by using it as a saturable absorber to modelock lasers at wavelengths longer than 1.55 μm.…”

“…While graphene-based fiber lasers have been mode locked at 1 and 1.5 μm, [3][4][5][6][7] there are only a few reports of graphene as a saturable absorber at 2 μm, such as: two Q-switched lasers, 11,19 a Q-switched and mode-locked laser, 3 a modelocked solid-state laser, 10 and one (recent) report of graphene's use in mode-locked fiber lasers at a wavelength greater than 1.6 μm.…”