RESUMO
Mamyshev oscillators have pushed the frontiers in output parameters of ytterbium- and erbium-based ultrafast fiber oscillators in the spectral region around 1 µm and 1.5 µm within the last few years tremendously. In order to expand the superior performance toward the 2 µm spectral region, we present in this Letter an experimental investigation of the generation of high-energy pulses by a thulium-doped fiber Mamyshev oscillator. Generating highly energetic pulses is enabled by a tailored redshifted gain spectrum in a highly doped double-clad fiber. The oscillator emits pulses with an energy of up to 15 nJ, which can be compressed to 140 fs.
RESUMO
An ultrafast thulium-doped fiber laser with stretched-pulse operation has been realized and investigated. The passively mode-locked oscillator emitted 119 fs pulses at a peak wavelength of 1912 nm. A normal-dispersion fiber with a high numerical aperture and small core was used for intracavity dispersion management and external compression. Numerical simulations were performed and are in good agreement with the experimental results.
Assuntos
Lasers , Fibras Ópticas , Fenômenos Ópticos , Túlio/química , Ondas de Rádio , Fatores de TempoRESUMO
We report on monotonically positively chirped pulse operation of a hybridly mode-locked thulium fiber laser. Dispersion management was realized with a small-core, high-NA fiber providing normal dispersion in the 2 µm wavelength region. The laser delivered pulses with 0.7 nJ energy at the 1927 nm center wavelength and sub-500-fs pulse duration after compression.
RESUMO
We investigated of the output characteristics of a spectrally filtered stretched-pulse thulium fiber laser in dependence of cavity dispersion and pump power. The experimental results together with corresponding theoretical modeling allow for a deeper insight into the pulse shaping mechanisms.
RESUMO
We report on chirped-pulse amplification of an ultrafast thulium-doped fiber laser. Pulses with an energy of 3.3 nJ and a bandwidth-limited pulse duration of 195 fs could be amplified to 151 nJ, which corresponds to an average power of 5.7 W at 37.6 MHz pulse repetition rate. The maximum output power was limited by the available pump power. The pulses could be dechirped to a duration of 258 fs.
RESUMO
We report on stretched-pulse operation of a thulium-doped fiber laser. The laser generated pulses at a center wavelength of 1974 nm with an energy of 4 nJ that could externally be compressed to a duration of 173 fs.
Assuntos
Desenho Assistido por Computador , Lasers , Modelos Teóricos , Fibras Ópticas , Túlio/química , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de RadiaçãoRESUMO
The wavelength dependent measurement of the relaxation oscillation frequency in a laser oscillator allows the study of the three- and four-level nature of the active material. Accordingly we present a tunable thulium doped fiber laser that covers the transition from three- to four-level operation at 2025 nm, characterized by the vanishing occupation of the terminal laser level. The laser is tunable from 1864 nm to 2075 nm with a linewidth below 0.3 nm. A maximum output power of 3.8 W at 1930 nm was achieved with a slope efficiency of 33.6% and an absorbed pump power of 17.5 W. Absorption and emission cross sections were derived over the tuning range by an intracavity measurement method.
Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers , Oscilometria/instrumentação , Túlio/química , Desenho de Equipamento , Análise de Falha de Equipamento , RadiometriaRESUMO
A femtosecond fiber laser based on thulium-doped double-clad silica fiber with an internal dispersion compensation is presented that generates pulses at a center wavelength of 1976 nm with an energy of 4.3 nJ and a duration of 1.2 ps. The dechirped pulse duration is 294 fs. The pulse energy is more than 2 orders of magnitude above the pulse energy demonstrated previously. Mode locking is achieved using additive pulse mode locking, and dispersion compensation is facilitated by a grating stretcher arrangement.