A topical review of numerical and experimental studies of supercontinuum generation in photonic crystal fiber is presented over the full range of experimentally reported parameters, from the femtosecond to the continuous-wave regime. Results from numerical simulations are used to discuss the temporal and spectral characteristics of the supercontinuum, and to interpret the physics of the underlying spectral broadening processes. Particular attention is given to the case of supercontinuum generation seeded by femtosecond pulses in the anomalous group velocity dispersion regime of photonic crystal fiber, where the processes of soliton fission, stimulated Raman scattering, and dispersive wave generation are reviewed in detail. The corresponding intensity and phase stability properties of the supercontinuum spectra generated under different conditions are also discussed.

Supercontinuum generation in photonic crystal fiber

This paper gives the 2010 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. The 2010 adjustment takes into account the data considered in the 2006 adjustment as well as the data that became available from 1 January 2007, after the closing date of that adjustment, until 31 December 2010, the closing date of the new adjustment. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2010 set replaces the previously recommended 2006 CODATA set and may also be found on the World Wide Web at physics.nist.gov/constants.

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CODATA Recommended Values of the Fundamental Physical Constants: 2006

The rise in output power from rare-earth-doped fiber sources over the past decade, via the use of cladding-pumped fiber architectures, has been dramatic, leading to a range of fiber-based devices with outstanding performance in terms of output power, beam quality, overall efficiency, and flexibility with regard to operating wavelength and radiation format. This success in the high-power arena is largely due to the fiber’s geometry, which provides considerable resilience to the effects of heat generation in the core, and facilitates efficient conversion from relatively low-brightness diode pump radiation to high-brightness laser output. In this paper we review the current state of the art in terms of continuous-wave and pulsed performance of ytterbium-doped fiber lasers, the current fiber gain medium of choice, and by far the most developed in terms of high-power performance. We then review the current status and challenges of extending the technology to other rare-earth dopants and associated wavelengths of operation. Throughout we identify the key factors currently limiting fiber laser performance in different operating regimes—in particular thermal management, optical nonlinearity, and damage. Finally, we speculate as to the likely developments in pump laser technology, fiber design and fabrication, architectural approaches, and functionality that lie ahead in the coming decade and the implications they have on fiber laser performance and industrial/scientific adoption.

High power fiber lasers: current status and future perspectives [Invited]

The history, fabrication, theory, numerical modeling, optical properties, guidance mechanisms, and applications of photonic-crystal fibers are reviewed

Photonic-Crystal Fibers

A review on the latest developments on graphene, written from the perspective of a chemist, is presented. The role of chemistry in bringing graphene research to the next level is discussed.

The chemistry of graphene

A laser with a ring resonator that incorporates a nonlinear antiresonant loop is proposed and analyzed. With computer simulation it is shown that the mode-locking process is self-starting and that, when the laser is properly designed, gain-bandwidth-limited pulses can be obtained. Passive mode-locked, bistable, and chaotic solutions are found to depend on the design parameters of the model.

Self-starting mode-locked laser with a nonlinear ring resonator.

A bismuth-doped fibre laser emitting at wavelengths within the second transparency window of silica fibres is fabricated. It is shown that Bi-doped aluminium-free phosphogermanosilicate fibres pumped in the regions of 800 and 1200 nm have the amplification band at 1275—1375 nm.

Bi-doped fibre lasers and amplifiers emitting in a spectral region of 1.3 μm

We have fabricated, to our knowledge, the first rectangular cross-section multicore fiber with eight cores arranged in a line. We have shown that the rectangular cross-section remains practically unchanged during the fiber-drawing process. The heterogeneous version of the proposed fiber design could be beneficial for crosstalk reduction because of the low influence of fiber bends on crosstalk between neighboring cores.

Multicore fiber with rectangular cross-section.

We present a composite optical fiber with a Er/Yb co-doped phosphate-glass core in a silica glass cladding as well as cladding pumped laser. The fabrication process, optical properties, and lasing parameters are described. The slope efficiency under 980 nm cladding pumping reached 39% with respect to the absorbed pump power and 28% with respect to the coupled pump power. Due to high doping level of the phosphate core optimal length was several times shorter than that of silica core fibers.

Phosphate-core silica-clad Er/Yb-doped optical fiber and cladding pumped laser.

Femtosecond pulse amplification in Er/sup 3+/-doped single-mode optical fibres has been experimentally investigated. The effect of amplified pulse compression from 80 to 55 fs has been observed. The amplified pulse energy was evaluated as 5 nJ. Maximum gain for the amplified signal was 26 dB.<
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E. M. Dianov

Papers

Self-starting mode-locked laser with a nonlinear ring resonator.

Bi-doped fibre lasers and amplifiers emitting in a spectral region of 1.3 μm

Multicore fiber with rectangular cross-section.

Phosphate-core silica-clad Er/Yb-doped optical fiber and cladding pumped laser.

Amplification of femtosecond pulses in Er/sup 3+/-doped single-mode optical fibres