Jakub Boguslawski

Graphene Oxide vs. Reduced Graphene Oxide as saturable absorbers for Er-doped passively mode-locked fiber laser

In this work we demonstrate comprehensive studies on graphene oxide (GO) and reduced graphene oxide (rGO) based saturable absorbers (SA) for mode-locking of Er-doped fiber lasers. The paper describes the fabrication process of both saturable absorbers and detailed comparison of their parameters. Our results show, that there is no significant difference in the laser performance between the investigated SA. Both provided stable, mode-locked operation with sub-400 fs soliton pulses and more than 9 nm optical bandwidth at 1560 nm center wavelength. It has been shown that GO might be successfully used as an efficient SA without the need of its reduction to rGO. Taking into account simpler manufacturing technology and the possibility of mass production, GO seems to be a good candidate as a cost-effective material for saturable absorbers for Er-doped fiber lasers.

Dissipative soliton generation in Er-doped fiber laser mode-locked by Sb 2 Te 3 topological insulator

We report on the generation of dissipative solitons in an Er-doped fiber laser mode-locked by antimony telluride (Sb 2 Te 3) topological insulator in the near-zero dispersion regime. Layers of Sb 2 Te 3 were deposited on a side-polished (D-shaped) fiber using a pulsed magnetron sputtering technique. Sub-170-fs pulses with 34-nm full width at half-maximum (FWHM) and 0.21 nJ of pulse energy were obtained from an all-fiber, ring-shaped laser cavity after the compression in a single-mode fiber.

Investigation on pulse shaping in fiber laser hybrid mode-locked by Sb 2 Te 3 saturable absorber

We report a study on a hybrid mode-locked fiber laser with two saturable absorbers: slow and fast, integrated in a single device. Amorphous antimony telluride (Sb(2)Te(3)) layer was deposited on side-polished fiber to form the slow saturable absorber due to the third order nonlinear susceptibility of Sb(2)Te(3). Additionally, an unsymmetrical design of the device causes polarization-dependent losses and together with polarization controller allows to use a nonlinear polarization evolution to form the artificial fast saturable absorber. Sub-200 fs soliton pulses with 0.27 nJ of pulse energy were generated in the hybrid mode-locked Er-doped fiber laser. Differences in the dynamics of mode-locked laser are further investigated with the use of slow and fast saturable absorbers solely, and compared with the hybrid device. Joint operation of two saturable absorbers enhances the laser performance and stability. The conducted experiments allowed to define roles of each mechanism on the pulse shaping in the laser cavity.

168 fs pulse generation from graphene-chitosan mode-locked fiber laser

We propose new graphene-chitosan solution as a saturable absorber for a mode-locked Erbium-doped fiber laser. We demonstrate stable, mode-locked operation with pulse as short as 168 fs, which are the shortest pulses generated from an Er-doped fiber laser with the use of graphene so far. Graphene-chitosan solution was obtained in soluble forms by the addition of the acetic acid. The ring laser is able to generate optical solitons centered at 1554 nm wavelength with 15.2 nm bandwidth and 63 MHz repetition rate.

Sb 2 Te 3 -deposited D-shaped fiber as a saturable absorber for mode-locked Yb-doped fiber lasers

We present a study on a antimony telluride (Sb2Te3)-deposited side-polished fiber device as a saturable absorber for Yb-doped mode-locked fiber lasers. Thin layers of Sb2Te3 with variable length were deposited by a pulsed magnetron sputtering technique. We demonstrate measured characteristics of the device and show that it can be treated as a hybrid component - tunable polarizer with saturable absorption properties. The polarizing extinction ratio varies from 1.5 dB up to 17.1 dB with increasing length of the deposition. The fiber components were employed in all-normal Yb-doped fiber cavities. All devices enabled for mode-locked operation by means of hybrid mode-locking or nonlinear polarization evolution mechanism. In particular, the laser with 2 mm long Sb2Te3 absorber emitted 5.9 ps pulses with 4 mW of average output power.

All-polarization-maintaining-fiber laser Q-switched by evanescent field interaction with Sb2Te3 saturable absorber

Abstract. We report on the generation of 152-nJ Q-switched pulses in all-polarization-maintaining Er-doped fiber laser. The laser is passively modulated by the antimony telluride (Sb2Te3) layer sputtered on a surface of the side-polished fiber in order to exploit the evanescent field interaction in optically nonlinear material. The laser cavity is designed in an extremely simple way comprising, in addition to fibers, only one component and the saturable absorber, forming a robust, compact, and stable source of short pulses. The repetition rate might be tuned from 42 kHz up to 132 kHz. The shortest recorded pulse duration was the 857 ns.

80 fs passively mode-locked Er-doped fiber laser

In this paper, 80 fs pulse generation from an all-fiber Er-doped laser is reported. The laser is mode-locked by a nonlinear polarization evolution mechanism in a stretched-pulse regime. Ultrashort pulses are generated directly from a ring-shaped, dispersion-managed cavity with a repetition rate of 31.9 MHz and 0.47 nJ of pulse energy. The laser has an all-fiber design, including the dispersion compensation and external compression stages, forming a robust and compact device.

Power Scaling of an All-PM Fiber Er-Doped Mode-Locked Laser Based on Graphene Saturable Absorber

This paper presents the study on power scaling of an all-polarization maintaining (PM) fiber mode-locked laser using the multilayer chemical vapor deposition graphene/poly(methyl methacrylate) composite as a saturable absorber by changing the coupling ratio of the laser output coupler. Pulses with the duration of 148 fs were generated using 10% output coupler, which are the shortest pulses obtained from mode-locked erbium doped fiber laser working in anomalous dispersion regime, additionally the highest average output power of 15.66 mW was achieved by applying 70% output coupler. All-PM fiber resonator configuration provides self-start and stable operation. To our knowledge, this is the first comprehensive study of power scaling of erbium doped fiber laser with graphene saturable absorber. Conducted experimental work is in very good agreement with numerical simulations.

Sb2Te3 topological insulator based saturable absorber for Er-doped mode-locked fiber lasers

We present an Er-doped fiber mode-locked laser based on an evanescent field interaction with the Sb2Te3 topological insulator. The saturable absorber (SA) consist of a bulk piece of Sb2Te3 material placed on the side-polished fiber in the presence of UV curable polymer. The measured SA optical parameters like: linear absorption, modulation depth and non-saturable loses were of 50%, 6% and 43%, respectively. The SA was spliced into the ring laser cavities characterized by the all-anomalous, all-normal and balanced dispersion. Such laser resonators allowed for optical solitons, dissipative solitons and Gaussian pulses generation with 3dB bandwidth of 8.5 nm, 37 nm and 17 nm, respectively.

2 µm ultrafast fiber laser modelocked by mechanically exfoliated Sb2Te3

We demonstrate the usage of a saturable absorber material - antimony telluride (Sb2Te3) for efficient mode-locking of a Thulium-doped fiber laser. The Sb2Te3 layers were obtained by mechanical exfoliation and transferred onto the fiber ferrule. The all-fiber laser was capable of generating optical solitons with the full width at half-maximum of 4.5 nm centered at 1945 nm, with 39.5 MHz repetition rate and more than 60 dB signal to noise ratio. The pulse energy of the generated 890 fs pulses was at the level of 30 pJ. Our experiment showed that Sb2Te3 saturable absorbers are suitable for the operation in 2 μm bandwidth.