Jerome Lhermite

75 W 40% efficiency single-mode all-fiber erbium-doped laser cladding pumped at 976 nm

Optimization of Yb-free Er-doped fiber for lasers and amplifiers cladding pumped at 976xa0nm was performed in this Letter. The single-mode fiber design includes an increased core diameter of 34xa0μm and properly chosen erbium and co-dopant concentrations. We demonstrate an all-fiber high power laser and power amplifier based on this fiber with the record slope efficiency of 40%. To the best of our knowledge, the achieved output power of 75xa0W is the highest power reported for such lasers.

High power, continuous-wave ytterbium-doped fiber laser tunable from 976 to 1120 nm.

We report on a linearly-polarized, continuous-wave Ytterbium-doped fiber laser continuously tunable on the fly over an unprecedented emission bandwidth ranging from 976 nm to 1120 nm and delivering a minimum of 10 W and a maximum of 41 W. Additionally, the bandwidth of the system can be tuned from 100 pm to more than 1 nm at all wavelengths.

High-energy femtosecond fiber laser at 976 nm

We report on a passively mode-locked fiber laser emitting around 976nm. The self-starting mode locking is achieved in an unidirectional ring cavity by means of nonlinear polarization evolution. Stable single-pulse operation is observed for 480mW of average output power. This all-normal dispersion laser generates naturally chirped pulses with 1ps duration. The repetition rate is 40.6MHz, resulting in 12nJ pulse energy. External compression using bulk grating shortens the pulse duration down to 286fs.

Mode-locked 0.5 μJ fiber laser at 976 nm.

We report on high-energy femtosecond pulse generation from an ytterbium-doped rod-type fiber oscillator emitting around 976 nm. Self-starting and stable single-pulse operation are demonstrated with 4.2 W of average output power at a repetition rate of 8.4 MHz. The resulting energy level reaches 0.5 μJ. Because of the all-normal dispersion of the laser cavity, output pulses are naturally chirped with a duration of 14 ps. External compression using diffraction gratings shortens the pulse duration down to 460 fs.

11–18 GHz continuously tunable repetition rate picosecond laser source at 1030 nm

Electro-optical combs generated from continuous-wave sources through amplitude and phase modulations have the potential to generate picosecond pulses with multi-GHz tunable repetition rates. They find applications in polarized Gamma ray production [1], imaging and picosecond acoustics. However, the development of such combs is mainly carried out with 1.5 μm laser sources [2, 3]. Only few developments exist so far at the Ytterbium gain window around 1 μm, where power scaling towards high average power and high energy level is obvious. In this talk, we will report on the development of a picosecond laser system operating at 1030 nm with a continuously tunable repetition rate from 11 to 18 GHz at a W-level average power.

Generation of picosecond laser pulses at 1030 nm with gigahertz range continuously tunable repetition rate.

We report on a watt range laser system generating picosecond pulses using electro-optical modulation of a 1030 nm single frequency low noise laser diode. Its repetition rate is continuously tunable between 11 and 18 GHz. Over this range, output spectra and pulse characteristics are measured and compared with a numerical simulation. Finally, amplitude and residual phase noise measurements of the source are also presented.

Pumping Yb:doped Bulk Materials with 976-nm Fiber Lasers

Advanced Solid State Lasers (ASSL)

500 nJ femtosecond fiber laser at 976 nm

Yb-doped fibers pumped at 976 nm will naturally amplify radiation in the 1020–1080 nm spectral bandwidth. Alternatively, pumping at 915 nm allows producing emission at 976 nm under specific conditions exploiting the three-level operation [1]. Recently, an Yb-doped fiber laser delivering up to 94 W at 976 nm in the continuous-wave regime has been demonstrated [2, 3]. Based on a similar approach, a millijoule-class laser at 976 nm operating in the Q-switch regime with up to 70 W average power has been achieved [4].

High gain Yb:CaF 2 amplifier pumped by a high brightness Ytterbium doped fiber laser operating at 976nm

The recent development of a high-power diffraction-limited fiber laser operating at 976 nm [1,2] offers an intriguing prospect of a breakthrough pumping technology and can supplant the current direct-diode pumping technology for high single-pass gain amplifiers. In this contribution we report on a significant single-pass small signal gain enhancement in an Yb:CaF2 crystal at room-temperature.

40 W narrow-bandwidth ps Yb-doped fiber laser at 976 nm and frequency conversion to 488 nm

Some applications may require laser specifications that result from a trade off between the antagonist features of narrow spectral line and high peak power. A solution may consist in invoking non-linearities in an optical fiber amplifier and more specifically the spectral compression [1]. In this contribution, we demonstrate for the first time the generation of a very high spectral brightness and high intensity fiber laser operating at the exotic wavelength of 976 nm. The present system provides therefore an optimal infrared source for frequency conversion to 488 nm and 325 nm.