All-fiber passively mode-locked thulium-doped fiber ring laser using optically deposited graphene saturable absorbers

Abstract

An all-fiber passively mode-locked thulium-doped fiber ring oscillator is constructed using optically deposited few layer graphene micro-sheets as the saturable absorber (SA). The mode-lock operation was achieved by 130-mW pump power at 1.5-μm. The fiber oscillator produces 2.1-ps soliton pulse output with 80-pJ per pulse energy. The 3-dB bandwidth of the laser output was measured as 2.2-nm. The RF signal-to-noise ratio of 50-dB and sub 20-Hz 3-dB bandwidth of the laser output confirms the stable laser operation with low time jittering. This paper shows that graphene can be an effective saturable absorber for the development of mid-IR fiber mode-locked laser.

Low Noise, Mode-Locked 253 MHz Tm/Ho Fiber Laser With Core Pumping at 790 nm

“…While Tm based femtosecond soliton mode-locked lasers have been demonstrated in configurations with different saturable absorbers, semiconductor saturable Bragg reflectors [19], graphene [20], [21], carbon nano-tubes [14], [22], repetition rates were below 100 MHz. Although seminal work based on saturable Bragg reflectors at a repetition rate of 334 MHz [23] and 1 GHz [24] was reported, corresponding pulse durations were closer to picoseconds.…”

Passively harmonic mode locking in ytterbium-doped fiber laser with graphene oxide saturable absorber

“…16 For 2-μm region wavelength, Wang et al reported using a few layers of graphene micro-sheets as the SA and constructed an all-fiber passively mode-locked thuliumdoped fiber (TDF) ring oscillator with a central wavelength of 1953.3 nm. 17 All the above show that the graphene indeed has a wavelength-independent SA, which could be exploited to mode lock fiber lasers with various operating wavelengths. 1 The graphene oxide (GO) is an atomically thin sheet of carbon covalently bonded with the functional groups containing oxygen.…”

“…Compared with the semiconductor saturable absorber mirrors [7][8][9] and carbon nanotubes, [10][11][12] graphene as the saturable absorber shows some terrific properties, which includes lower saturation intensity, less nonsaturable loss, higher damage threshold, larger absorption (2.3% per single graphene sheet), and wavelength independence from visible to infrared due to its zero bandgap property. 1 Up to now, many investigations [13][14][15][16][17] have been reported on the GSA-based mode locking fiber laser emitting in different regions of wavelengths. Zhang et al 13 and Popa et al 15 have reported 1550-nm region wavelength emitting from erbium-doped mode locking fiber laser, with the pulse duration of 415 fs and sub-200 fs, respectively.…”

Soliton building from spontaneous emission by ring-cavity fiber laser using carbon nanotubes for passive mode locking

“…7 Graphene [8][9][10] and nanoscale graphite 11,12 materials based on CNTs have attracted much attention because of their high optical nonlinearity and fast recovery time when used as an SA in a mode-locked erbium-doped fiber laser (EDFL) for femtosecond/picosecond pulse generation. [13][14][15][16][17][18] Because SWCNTs possess subpicosecond recovery times and broad absorption spectra, active fibers doped with Yb: KLuW operating at a wavelength of 1000 nm, 19 a praseodymium-doped fiber operating at 1300 nm, 20 a ytterbiumdoped fiber operating at 1064 nm, 21 and active fibers doped with Er þ3 operating at 1500 nm have been modelocked with SWCNT SAs. 22 Most recent studies on fiber lasers have focused only on the use of CNTs with erbium (Er) fiber lasers for generating short optical pulses at a 22 MHz repetition rate with a 50 kW peak power and a 1.1 ps pulse width 23,24 or a 39 MHz repetition rate with a 3.4 mW peak power and a 115 fs pulse width.…”