Showing papers by "Sergei Popov published in 2007"
TL;DR: The design constraints for tapered PCFs used for adiabatic soliton compression are discussed and over 15 times compression of pulses from over 830 fs to 55 fs duration at a wavelength of 1.06 lm is demonstrated.
Abstract: Improvements to tapered photonic crystal fiber (PCF) fabrication have allowed us to make up to 50 m long PCF tapers with loss as low as 30 dB/km. We discuss the design constraints for tapered PCFs used for adiabatic soliton compression and demonstrate over 15 times compression of pulses from over 830 fs to 55 fs duration at a wavelength of 1.06 μm, an order of magnitude improvement over previous results.
91 citations
TL;DR: The potential of frequency doubling of the non-polarized output at 1178nm in MgO doped periodically poled lithium niobate was demonstrated and resulted in 125mW average power at 589nm.
Abstract: We achieved a 0.2nm linewidth output at 1178nm with powers up to 6.4W in a linear 80m Bismuth-doped fiber cavity pumped by a 55W Yb fibre laser. The potential of frequency doubling of the non-polarized output at 1178nm in MgO doped periodically poled lithium niobate was demonstrated and resulted in 125mW average power at 589nm. The approach can be extended to a linearly-polarized large mode area format with under 0.1nm linewidth capable of scaling to Watts level in the 560-620nm range.
90 citations
TL;DR: In this paper, the first Stokes in a high-concentration GeO2 fiber Raman laser was generated by a 22 W thulium-doped fiber laser.
Abstract: We report 33% efficient generation of the first Stokes in a high-concentration GeO2 fiber Raman laser pumped by a 22 W thulium-doped fiber laser. An output power of 4.6 W at 2.105 µm is demonstrated.
31 citations
TL;DR: In this paper, the first Stokes in a high-concentration GeO2 fiber Raman laser with a 22 W Thulium doped fiber laser was demonstrated.
Abstract: We report on 33 % efficient generation of the first Stokes in a high concentration GeO2 fiber Raman laser pumped by a 22 W Thulium doped fiber laser. An output power of 4.6 W at 2.105 um is demonstrated.
28 citations
TL;DR: Numerical simulations of the system support the experimental measurements and also confirm the role of fiber dispersion in obtaining high-quality compressed pulses.
Abstract: We report the generation of 140 fs pulses with a peak power of up to 270 kW using a fiber pulse source based on a polarization-maintaining ytterbium-doped fiber amplifier and a semiconductor saturable absorber mirror mode-locked fiber laser seed. The seed laser pulses were amplified and chirped in the fiber amplifier and subsequently compressed in an external transmission grating pair. The use of a polarization-maintaining amplifier addresses nonlinear polarization-induced limitations to the obtainable compressed pulse duration and quality that can arise if isotropic fiber amplification is used. Numerical simulations of the system support the experimental measurements and also confirm the role of fiber dispersion in obtaining high-quality compressed pulses.
9 citations
06 May 2007
TL;DR: In this article, supercontinua spanning 320 -2400 nm have been generated in long photonic-crystal- fiber tapers with total average powers of over 3.5 W and spectral power densities in the blue of over 5 mW/nm.
Abstract: Supercontinua spanning 320 -2400 nm have been generated in long photonic-crystal- fiber tapers. Total average powers of over 3.5 W and spectral-power-densities in the blue of over 5 mW/nm are demonstrated. Use as a broadly-tunable pulse source is proposed.
7 citations
TL;DR: In this paper, a uniform high spectral brightness and peak power density all-fiber supercontinuum source was demonstrated with a nanosecond Ytterbium fiber laser and an optimal length PCF.
4 citations
06 May 2007
TL;DR: In this article, dispersion decreasing photonic-crystal-fibers were used for soliton compression at 1.06m mum and achieved compression ratios of over 15.
Abstract: We report dispersion decreasing photonic-crystal-fibers for soliton compression at 1.06 mum. Fibers 15-60 m long with dispersion varying from 40-0 ps.nm-1.km-1 were used to achieve compression ratios of over 15. Pulses of 655 fs were compressed to 43 fs solitons.
4 citations
TL;DR: In this paper, the authors extend the region of short wavelength operation of high power supercontinuum generation through four wave mixing in a cascaded fiber geometry where the dispersion of each fibre decreased on propagation.
Abstract: The enhancement of different non-linear processes in microstructured optical fibres can be achieved through manipulation of the dispersion characteristics of the fibre. This is demonstrated by extending the region of short wavelength operation of high power supercontinuum generation through four wave mixing in a cascaded fibre geometry where the dispersion of each fibre decreased on propagation. The technique is further refined in a demonstration utilizing long lengths of dispersion decreasing tapered microstructured fibres, where the supercontinuum extends to around 300 nm with spectral power densities in excess of 2 mW/nm in the uv. These long length tapers can also be utilized for adiabatic soliton pulse compression in new spectral regions, allowing the compression of 655 fs pulses to 45 fs.
3 citations
TL;DR: In this paper, a technique employing long lengths of tapered PCFs that allow efficient phase matched four wave mixing to the short-wavelength region was developed, which achieved spectral power densities as high as 5mW/nmin.
Abstract: Various techniques are described for the efficient non linear conversion of high power fibre laser sources. These include
the frequency doubling in periodically poled crystals of polarization preserving high power fibre Raman masteroscillator
power fibre amplifier schemes, or the frequency doubling of a high power, narrow line bismuth-doped fibre
laser, primarily for visible generation in the region of 589 nm. Above 2 microns where loss in silica based fibres
prohibits efficient Raman generation, the use of heavily doped (~75%) GeO 2 fibres has been demonstrated as an efficient
and effective all-fibre configuration to extend high power cw operation into the near infra red spectral region. For many
applications, high peak power multiple wavelengths are required simultaneously. The integration of pulsed fibre lasers
operating around 1 mm and photonic crystal fibre provides a simple mechanism to achieve this goal. Generally, the upper
wavelength limit of supercontinuum generation is restricted by propagation loss and this has a consequential effect of
inhibiting short wavelength generation through four wave mixing in the fibre. We have developed a technique employing
long lengths of tapered PCFs that allow efficient phase matched four wave mixing to the short wavelength region and
permits the generation of spectral power densities as high as 5mW/nmin the uv.
3 citations
02 Sep 2007
TL;DR: In this article, a 15-60m long, dispersiondecreasing tapered solid-core photonic crystal fibers were used for adiabatic soliton compression at 1.06µm wavelength.
Abstract: We report use of 15-60m long, dispersion-decreasing tapered solid-core photonic crystal fibers for adiabatic soliton compression at 1.06µm wavelength. 655fs input pulses were compressed to 43fs solitons.
06 May 2007
TL;DR: In this paper, a CW Er-ASE-source-pumped highly nonlinear fiber-based OCT system was presented, which can enable micron-scale OCT around low-scatter 1.8 mum region.
Abstract: We report on a fibre-system, based on CW Er-ASE-source-pumped highly nonlinear fibre. As low as -120 dBc/Hz intensity noise of the near-Gaussian >200 nm bandwidth was obtained. The source can enable micron-scale OCT around low-scatter 1.8 mum region.
TL;DR: In this paper, the development of simple, fibre integrated femtosecond soliton sources based on the propagation of CW noise through a highly nonlinear fibre is reported, and it is shown that pulse compression can be obtained in this format through the use of Raman amplification.
Abstract: The development of simple, fibre integrated femtosecond soliton sources based on the propagation of CW noise through a highly nonlinear fibre is reported. It is shown that pulse compression can be obtained in this format through the use of Raman amplification. A method of wavelength extension to the visible using microstructure is proposed.
06 May 2007
TL;DR: In this article, a Raman laser with an output power of 4.2 W at 2.1 μm was reported, based upon a 75 mol.% GeO2 doped fiber pumped with CW Thulium doped laser.
Abstract: We report a Raman laser with an output power of 4.2 W at 2.1 μm based upon a 75 mol.% GeO2 doped fiber pumped with CW Thulium doped fiber laser. Potential of 2.3 μm operation is discussed.
06 May 2007
TL;DR: In this paper, a Bismuth-doped fiber laser was used to achieve a lasing output of 1178 nm with a potential for frequency doubling to 589.6.
Abstract: 6.4 W lasing output at 1178 nm is obtained from a Bismuth-doped fiber laser pumped by 50 W CW Ytterbium fiber laser. Narrow, below 0.2 nm, linewidth shows a potential for frequency doubling to 589.