Rongyong Lin

Tunable and switchable multi-wavelength dissipative soliton generation in a graphene oxide mode-locked Yb-doped fiber laser

We report the generation of tunable single-, switchable and tunable dual-, and stable triple-wavelength dissipative solitons (DSs) in an all-normal-dispersion mode-locked Yb-doped fiber laser based on a graphene-oxide saturable absorber (GOSA) without additional components (such as optical filter, or fiber grating). The tunable single-wavelength DS have a wide wavelength-tunable range of 16.4 nm. The dual-wavelength DSs not only have a wavelength-tunable range (about 10 nm) but also have variable wavelength spacing (3.8-13.8 nm). The formation dynamics of the triple-wavelength DSs was also investigated experimentally. The different operations of tunable single-, switchable and tunable dual-, and stable triple-wavelength DSs depend on the strength of the cavity birefringence. The simple, compact all-fiber DS laser with lasing wavelength tunability and flexibility can meet great potential for applications.

A 2.95 GHz, femtosecond passive harmonic mode-locked fiber laser based on evanescent field interaction with topological insulator film

By utilizing the pulsed laser deposition (PLD) method, we fabricated a kind of microfiber-based topological insulator (TI) saturable absorber (SA) which has inherent merits of effective and robust properties. We also proposed a newly explanation for the impact of nonlinear effect of SA on the harmonic mode-locking (HML) behavior. Upon employing on the SA, we achieved stable fundamental mode-locking (FML) at central wavelength of 1562.4 nm with pulse duration as short as 320 fs. By adjusting the intracavity polarization state at maximum pump power of 395 mW, we obtained stable femtosecond harmonic soliton pulse generation with repetition rate of 2.95 GHz and output power of 45.3 mW. Our results demonstrated that the microfiber-based TI PLD film SA is a promising device for practical multi-GHz ultrashort pulses generation.

Soliton rains in a graphene-oxide passively mode-locked ytterbium-doped fiber laser with all-normal dispersion

We experimentally investigated soliton rains in an ytterbium-doped fiber (YDF) laser with a net normal dispersion cavity using a graphene-oxide (GO) saturable absorber (SA). The 195 m-long-cavity, the fiber birefringence filter and the inserted 2.5 nm narrow bandwidth filter play important roles in the formation of the soliton rains. The soliton rain states can be changed by the effective gain bandwidth of the laser. The experimental results can be conducive to an understanding of dissipative soliton features and mode-locking dynamics in all-normal dispersion fiber lasers with GOSAs. To the best of our knowledge, this is the first demonstration of soliton rains in a GOSA passively mode-locked YDF laser with a net normal dispersion cavity.

High order harmonic mode-locking in an all-normal-dispersion Yb-doped fiber laser with a graphene oxide saturable absorber

A high order passive harmonic mode-locking (HML) Yb-doped all-normal-dispersion fiber laser based on a graphene oxide saturable absorber has been experimentally demonstrated. For two different pump powers and different polarization states of the laser cavity, lower order and higher order HML have been achieved. The highest 30th-order harmonic (31.86 MHz) was achieved with subnanosecond pulse duration; this is transitional from a bunched multipulse state.

Bright and Dark Square Pulses Generated From a Graphene-Oxide Mode-Locked Ytterbium-Doped Fiber Laser

The observation of the bright pulses and dark square pulses in a graphene-oxide saturable absorber (GOSA) passively mode-locked ytterbium-doped fiber laser has been investigated experimentally. Bright pulses are achieved at a pump power of ~ 200 mW. However, the dark-square-pulse generation starts at a much higher pump power of ~ 450 mW. At the maximum pump power of 600 mW, the dark-square-pulse bunches and harmonic mode locking (HML) can be also obtained by tuning the polarization controller (PC) to different orientations. It is the first demonstration of the bunches and HML of dark square pulses in a GOSA passively mode-locked ytterbium-doped fiber laser with large normal dispersion cavity.

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

Abstract. We have demonstrated the dissipative solitons generated in an ytterbium-doped fiber laser cavity using graphene oxide as the saturable absorber. The lasing light, centered at 1077.2 nm, has a 3 dB spectral bandwidth of ∼1.12  nm. Under different launched pump powers and appropriate polarization orientations, harmonic mode-locked of second- and third-order pulse trains have been achieved; the corresponding 3-dB bandwidth and pulse duration have been detected.

Two different output states from an all-normal dispersion yetterbium-doped fiber laser using graphene-oxide as a saturable absorber

We have experimentally obtained two different applied output states from an all-normal dispersion yetterbium-doped fiber laser using graphene-oxide as a saturable absorber without additional components (like tunable filter, dispersion compensation), including the wavelength-switched mode-locking operation, and the dissipative soliton resonance (DSR) operation with high energy square pulses. These two experimental phenomena indicate that the graphene-oxide saturable absorber can be successfully used to realize different mode-locking states in a fiber laser by system-parameter management. The yetterbium-doped fiber laser in all-normal dispersion with flexible outputs can meet different application needs.