Progress in high average power ultrafast lasers

Abstract

The impact of femtosecond lasers across science and engineering has been significant. The one area which has so far proved hard to access for femtosecond lasers has been the combination of high peak power and high average power. This review seeks to highlight the issues which make high average power hard to achieve in many femtosecond systems, and looks at the routes that are now being taken to achieve the goal of high peak and high average power. Managing thermal and nonlinear effectsThe technological problems involved in producing high average power lasers and high peak power lasers are significantly different. In a high average power laser system, the principal problem is managing the thermal load within the laser, because any

Photodarkening-Induced Phase Distortions and Their Effects in Single-Channel and Coherently Combined Yb-Doped Fiber Chirped Pulse Amplification Systems

“…Coherently combined multi-channel amplifier systems also depend on the optical phase. This includes coherent beam combination (CBC) of femtosecond pulses [22]- [24]. The number of concepts and experimental demonstrations is increasing rapidly (e.g., [17], [25]- [29]), and femtosecond CBC systems are also commercially available [30].…”

How Size Determines the Value of Gold: Economic Aspects of Wet Chemical and Laser‐Based Metal Colloid Synthesis

“…Hence, althoughi nvestment costs for high powerl aser sources are quite high, an economic production of laser-generated nanoparticles is feasible by an increaseo fnanoparticle productivities to 550 mg h À1 in particulara tc ontinuouso peration. [46] While the decreasei na bsolutec osts forl aser-based nanoparticle synthesis is enabledb yc hoosing laser sources with ah igherp ower, reduction of costs fort he wet-chemical nanoparticle synthesis can be achieved by an increase of the rotor capacity used for ultracentrifugation over the standard value of 120 mL. Besides the variation of laser parameters, [29,40,41] such as pulse energy,l aser wavelength, pulse widthsa nd repetition rate, the target geometry can be optimized from thin gold foils to wires [42,43,44] as well as reconstruction of the batch ablation chamber to ac ontinuously workingf low chamber.…”

“…Furthermore,e ven cheaper laser systems with higherl aser power corresponding to higher nanoparticle productivities will be availablei nt he near future,i ft he trend in laser technology remains. [46] While the decreasei na bsolutec osts forl aser-based nanoparticle synthesis is enabledb yc hoosing laser sources with ah igherp ower, reduction of costs fort he wet-chemical nanoparticle synthesis can be achieved by an increase of the rotor capacity used for ultracentrifugation over the standard value of 120 mL. The increase of liquid capacity per centrifuge passage towards 1500 mL results in nanoparticle net productivityi ncreasef rom 35 mg h À1 towards 850 mg h À1 at ag old concentrationo f 800 mg L À1 (Figure 6b).…”

Using an intense laser beam in interaction with muon/electron beam to probe the noncommutative QED

“…In recent years the leaser average powers are about a few watts which are higher than the range of tens of milliwatts to watts for the average powers of ruby lasers in the early 1960s. However, recently some progress has been made to improved the average power of ultrafast lasers [35], for instance see [36][37][38][39]. Furthermore, the Compton back scattering has been also considered since 1980s to produce photon beams.…”