This year, in San Jose, California Western USA Photonics West by the American International Optoelectronic Science Engineering Society (SPIE) sponsored by Photonics West, the laser source engineering laser technology and industrial lasers (LASE) theme of the conference (Laser Source Engineering) sub-theme of the conference about Fiber Lasers XIII: technical discussions technology, Systems and Applications, has now become the first order by the SPIE Proceedings volume 9728, as part of the session on the following summary:
 

1. The Air Force Laboratory, by Iyad Dajani et al., entitled "Multi-kilowatt power scaling and coherent beam combining of narrow-linewidth fiber lasers".

This paper reports two power of about 1.5kW, bare efficiency and linewidth similar ytterbium-doped fiber amplifier. An amplifier 25 μm core diameter of an optical fiber and another optical fiber amplifier is used in core diameter is 20 μm. Both stimulated Brillouin scattering (SBS) is suppressed by a pseudo-random bit sequence (PRBS) phase modulation to achieve. This results in a larger core diameter fiber core power mode by instability (MI) limit, and in the small diameter fiber is not observed signs of MI. This makes it possible to use author mode instability threshold value higher fiber while maintaining a sufficiently narrow width to further enhance the power for beam combining. In addition, the combination of proven thermal gradient was applied using a phase modulation scheme can be further suppressed SBS experiments proved the PRBS with 2GHz clock speed drive 1kW amplifier. Finally, the seeds were relatively coherent phase modulation PRBS source and the white noise source beam combiner amplifier performance.
 

2. Thorlabs Company, by Reza Salem et al., entitled "23-kW peak power femtosecond pulses from a mode-locked fiber ring laser at 2.8µm" article.

Article reported the use of nearly 2 μm femtosecond fiber laser pumping dispersion design of step-index indium fluoride fiber, produce mid-infrared supercontinuum (SC). This supercontinuum from 1.25 μm to 4.6 μm, 1.8 octave span, the average output power of 270mW. The pump source is all-fiber femtosecond laser, which produces a repetition rate of 50 MHz sub - 100 fs laser pulses, with an average power of 570 mW. Zero-dispersion wavelength for generating a supercontinuum indium fluoride fiber is designed to be close to 1.9 μm, the length of the experiment two fibers preferably 30 cm and 55 cm is based on the results of numerical simulations. In both fiber length condition, results of spectral measurements and numerical simulation obtained good agreement emerged. Femtosecond pump mechanism is a key requirement to generate a coherent super continuous spectrum by simulation shows that: when using the same laser and fiber laser pump pulse width and energy, plus the quantum noise limit, supercontinuum is coherent. These results indicate that to achieve coherent, high repetition rate supercontinuum light source is very promising, and these two conditions are important for Fourier transform infrared spectrometer spectrum. In addition, the systems are continuous over the entire optical fiber core diameter similar structures can be easily integrated into a compact platform.
 

3. Institute of Applied Physics of the Russian Academy of Sciences, by Oleg Antipov et al., entitled "Low-threshold mode instability in Yb3+-doped few-mode fiber amplifiers: influence of a backward reflection".

This paper studies the core diameter of 8-10 μm ytterbium both experimentally and theoretically less mold protection temporal instability of polarization maintaining fiber amplifier in the fundamental mode. Record the pump power instability threshold 1-100W model, the authors found that when the output of the optical fiber after reflection or outside the presence of the reverse transmission beams, the threshold will be dramatically reduced; increase input signal bandwidth or power will resulting in increased threshold values. Numerical simulation reveals the self-consistency of the higher-order modes along with population growth and grating electronic transmission refractive grating in which the population is composed of raster mode interference field (excitation and non-excitation from ytterbium ions of different polarization) introduced of.
 

4. The Photoelectric Research Center of the University of Southampton, by Anna C. Peacock et al., entitled "Semiconductor optical fibers for nonlinear applications".

The semiconductor material embedded fiber geometry is to enhance the traditional optoelectronic functional fiber infrastructure, while allowing an important step to build a solid device with a new waveguide performance. In this article, the author developed an integrated all-optical device perspective, reviewed the progress made in the description of the semiconductor optical nonlinear transfer characteristic aspects. Nonlinear properties of this fiber have been high-speed all-optical wavelength conversion, modulation and continuous spectrum to produce the proof.
 

5. The US Naval Research Laboratory, by Colin C. Baker et al., entitled "Nanoparticle doping for improved Er-doped fiber lasers".

Nanoparticles (NP) is doped with erbium-doped fiber to improve the performance of a technology for high power laser applications. Because erbium ions are surrounded by aluminum atoms and oxygen atoms cage local environment during the synthesis of nanoparticles created by a chemical reaction, ion - energy exchange between ions and their harmful effects on the performance of the laser will be greatly reduced. Article reports the fabrication and measurement technology core and cladding doped nanoparticles pumped erbium-doped optical fiber. Resonance core pumped fiber bare slope efficiency is 80.4%, compared with the reported commercial liquid doped fiber record efficiency.
 

6. Fiber optics research center of the Russian Academy of Sciences, by E. M. Dianov et al., entitled "Bismuth-doped fibers and fiber lasers for a new spectral range of 1600-1800 nm".

From 1150 to this the near-infrared spectral range 1800nm, including 1250 and 1600 to 1500nm to 1800nm ​​these two no effective rare-earth doped fiber laser bands exist, bismuth-doped fiber is promising activation in these two bands medium. Both spectral range there is great interest in some applications, particularly in the field of optical fiber communication. Earlier, the authors developed a run in 1250 to 1500nm band of bismuth-doped fiber lasers and amplifiers. Now, they reported that the latest research-doped bismuth 1600-1800nm ​​within the fiber and fiber lasers in a new spectral range results.
 

In conclusion, the authors believe first created to provide optical gain in the spectral range 1600-1800nm ​​bismuth-doped fiber, but also the influence of bismuth doping level and the synthesis temperature unbleached loss. They also believe that the development of the first run 1625-1775nm bismuth-doped fiber laser, efficiency and maximum output power of these lasers to obtain about 30%, respectively, and 2W. Now, bismuth-doped fiber laser can run 1150-1775nm broadband spectral range covering the entire low-loss optical fiber telecommunications window (O, E, S, C, L and U bands) shown in Figure 1. The article also get their first run in the 1680nm multiplier results bismuth-doped fiber laser.