The pulse duration could be adjusted from 2ns to 200ns. In this paper, a laser with a wavelength of 1030 nm, pulse duration of 19 ps, repetition rate of 10 khz, and burst regime consisting of either four or. Over the last five years, material processing with femtosecond pulses in the range of 300 to 900 fs has gained in popularity due to the small heataffected zone haz and increased energy penetration depth resulting from the high laser pulse intensity. Dec 11, 2017 in this research, by adopting an alternative novel approach to ultra short giant pulse generation which basically originated from difficulties with traditional employed methods, an optimized eryb codoped doubleclad fiber amplifier is applied to boost output average power of singlemode output pulses to a high level of 2w at 1.
If such true power scalability is given, the laser performance can be increased within a wide range of output powers without relying on new materials e. See the article on high power fiber lasers and amplifiers for more details. Apr 23, 2018 high power laser system generates ultrashort pulses of light covering a large share of the midinfrared spectrum. Fiber lasers, which consist of ideal waveguides of optical. Request pdf on jan 1, 2006, akira shirakawa and others published power scaling of cw and ultrashort pulse fiber lasers find, read and cite all the research you need on researchgate. Industrial laser systems continue to evolve in terms of power levels, brightness and mode of operation. Ultrashort laser pulse phenomena book pdf download. Highpower laser system generates ultrashort pulses of light. This results in permanent material changes, largely independent of the processed glass, and it is of particular relevance for cleaving applications. Ultrashort pulse simulations with the rp fiber power software. A conventional bulkgrating compressor was used to remove the linear chirp. Compression of cepstable multimj laser pulses down to 4. Ultrashort pulse formation and evolution in modelocked fiber.
Apr 16, 2018 a primary shortcoming of modelocking free laser sources is the achievable pulse duration. First, the progress of ultrashort pulse fiber lasers is mentioned in sect. Oct 20, 20 high power fibre lasers are in demand for industrial, defence and scientific applications. In this paper we overview the physical mechanisms relevant for up scaling the peak power in hollow fiber pulse compressors. Innoslab the concept for power scaling power scaling at 1. Fibre is an engineerable, lowcost laser medium that is combinable in high power, robust laser circuits the specification for a wakefield accelerator can be met by combining large numbers of fibre lasers fibre laser system engineering is a young technology, so much more to come research areas focus on psfs scaling. A nondistributed scalar model solving the nonlinear schrodinger equation is implemented to study the starting behavior and intracavity dynamics numerically. Industrial grade fibercoupled laser systems delivering. Coherent addition of fiberamplified ultrashort laser pulses.
The system demonstrates a fiber laser, based on passive mode locking using a saturable absorber, capable of producing ultrashort pulses sample. The average maximum power of 285 mw and a pulse energy of 8. Prospects for peak power scaling of tmdoped fiber cpa systems. The system incorporates a novel pulse source based on a low power pulsed semiconductor laser, and which shows the compatibility of high power fiber technology with compact, low cost sources. Industrial ultrashort pulse usp diodepumped solidstate and fiber lasers are now being. Future laser system merlin ch 4 space lidar airborne spaceborne. This work is focused on the investigation of the viability of such fibers for the scaling of average power and pulse peak power in fiber based ultrashort pulse systems.
Compact and ultrastable passively modelocked fiber oscillators represent an ideal seed source for high performance femtosecond fiber amplification systems, which have been scaled towards kwlevel average power and pulse energies well above the. The laser light can have very good beam quality even. To saturate the absorption of the nr array, they used a 1555 nm pulsed laser with a 500 ps pulse duration, a repetition rate of 100 khz, and an average output power of. They can be used for laser cutting, drilling, laser marking or surface treatment applications. Ultrashort pulsed lasers provide uniquely detailed access to the ultrafast dynamics of physical, chemical, and biological systems, but only a handful. Ultrashort pulse fiber lasers and their applications. The pslasers and fslasers enable cold processing of the material even at moderate average power, meaning that there is practically no heat input on the workpiece. High power femtosecond fiber laser systems high power femtosecond fiber laser systems limpert, jens 20030619 00. Several systems based on this phenomenon allowed the generation of ultrashort pulses at different wavelengths and in different type of fibers stepindex, pcf. Theory of laser energy harvesting at femtosecond scale. The second group has ultrashort pulse widths that are nanoseconds or less. Ultrashortpulsed laser sources with kilowatt power for.
Using the first method, we succeeded to generate 17w average power of linearly chirped parabolic pulses at 75 mhz repetition rate and diffractionlimited. Together with the good focusability, high pulse peak powers and average powers, this allows for. Efficient heat dissipation and guided light propagation in optical fibers make fiber lasers attractive for average output power scaling to multikw level in the single transverse mode regime. But also in terms of the available pulse energies and peakpowers, state of theart fiber lasers have become competitive to other solidstate laser concepts. Fiber based ultrashort pulse laser systems at ultrahigh. Power scaling of ultrashort pulse fiber laser systems. Splitting and combination is achieved by polarization cubes, i. Further work will address power scaling and implementation of the laser in an integrated demonstrator system, which. Ultrashort pulse lasers usp lasers which provide sufficient output power for industrial applications offer pulse lengths in the range from some 10 picoseconds to some 100 femtoseconds.
Highpower fiber lasers and amplifiers rp photonics. High power femtosecond fiber chirped pulse amplification. High power femtosecond lasers wiley online library. Ultrashort laser pulses allow for involume processing of glass through nonlinear absorption. Advances in high power, short pulse, fiber laser systems and.
For a pulse duration of 800 fs at a wavelength of 1030 nm the repetition rate has been varied from 50 khz to 975 khz, and pulse energies from 10. These properties result in compact, singlepass and even monolithic ultrashort pulse laser systems, which are capable of emitting average powers up to the kilowatt level. Today, this potential is only realized in refractive surgery and some femtosecond micromachining. After power scaling, the group velocity dispersion and thirdorder dispersion, generated in fiber stretcher and amplifiers, are compensated by a grism compressor, outputting a 2w, 180fs pulse train.
Oct 30, 2014 the idea of an ultrashort pulse is one of the most interesting and developed new concepts in femtotechnology today generally, when we say ultra short pulse, were talking about ultrashort pulse laser technology, but this term can encompass any area of the electromagnetic spectrum and indeed, its conceivable that there could be an ultra short pulse of air, water, or other. However, further average power scaling is limited by transverse mode instabilities. An interesting question is whether claddingpumped fiber lasers and amplifiers are power scalable. Reliable turnkey high power ultrafast laser sources are required for a variety of applications in science, industry, and medicine.
Recent advances in power scaling of highpower optically. Jun 19, 2003 fiber laser systems offer unique properties for the amplification of ultrashort pulses to high powers. Pdf allfiber similariton ultrashort pulse laser systems. High power chirallycouplecore ccc fiber lasers for. Compact ultrafast oscillators and high performance. Parameter scaling of ultrashort pulse lasers power scaling beyond 1 kw energy scaling to mj range pulse shortening below 500 fs. Ultrashort pulse laser technology ultrashort pulse lasers are an enabling technology for a whole range of fundamental and applied research areas as well as industrial applications. Many applications use a fiber laser machine with continuouswave operation. Thuliumdoped fiber chirpedpulse amplification system. Here, we present a laser system delivering a pulse peak power of 2 gw and a nearly transformlimited pulse duration of 200 fs in combination with 28. The mfpt20mopa pulsed fiber lasers series products are aircooled, maintenance free fiber lasers with a compact and rugged package. Allfiber highpower monolithic femtosecond laser at 1. In this dissertation we present a detailed study of using this novel ccc fiber technology for high pulse energy and high average power systems, in particular for use in different types of coherentlycombined fiber laser arrays, where compatibility of ccc fiber technology with monolithic integration becomes an enabling factor for constructing. By a simple analysis, we show that the effective length as well as the cross.
We report on a high power fiber optical frequency comb consisting of a 250mhz modelocked fiber laser and a threestage cascaded fiber chirped pulse amplification system. A general answer is not possible owing to the multitude of applied techniques and the dependence on the specific requirements, e. It is shown how the propagation of ultrashort pulses e. The performance of a dissipativesoliton laser agree well with simulations that assume singlemode propagation, and scales correctly with mode area from equivalent smf lasers. We report on a novel approach of performance scaling of ultrafast lasers by means of coherent combination. Advances in high power, short pulse, fiber laser systems. A passively modelocked ultrashort pulse fiber laser using the intensitydependent absorption element has made great progress using a new type of saturable absorber with a nanocarbon material. In this paper, we report on the design of a compact and robust allpolarizationmaintaining pm fiber system entirely based on. Highpower femtosecond fiber laser systems, proceedings of. Another type of fiber laser is the fiber disk laser. Osa several new directions for ultrafast fiber lasers invited.
We report here on a research prototype, high power femtosecond fiber chirped pulse. Qswitched high power fiber laser high power fiber resonator with external qswitches pulse duration of 8 ns fwhm. The average output power is up to 20w and the highes pulse energy is 0. To overcome these limitations, the use of volume cbgs for pulse stretching and compression has been pro. Novel ultrashort pulse fiber lasers for micromachining applications. Rarely do they produce pulses shorter than a few picoseconds, and more economical systems are limited to tens of picoseconds.
High power fiber lasers and fiber amplifiers are nearly always realized with rareearthdoped doubleclad fibers, which are pumped with fiber coupled high power diode bars or other kinds of laser diodes. Today, solidstate lasers come in two broad categories. Rp photonics encyclopedia fiber lasers, fibre, rare. Pulse compression of a highpower thin disk laser using rod. Systems based on modulated cw light are limited by the bandwidth and power of electrooptic modulators and their drivers.
As a consequence ultrafast fiber laser systems with novel performance are in reach, i. Present and future almantas galvanauskas, university of. Power scaling of cw and ultrashortpulse fiber lasers. Ultrashortpulse laser pulse duration in the range of picoseconds 10 12 s and femtoseconds 1015 s the smaller they are, the stronger they get the immense power of the laser pulses is due to the fact that they are incredibly short. We report on an industrial fiber delivered laser system producing ultra short pulses in the range of a few picoseconds down to a few hundred femtoseconds with high average power suitable for highprecision micromachining. By understanding what pulse width is the correct pulse width to utilize these unique benefits can be a tricky adventure. They are also known as ultrafast lasers owing to the speed at which pulses turn on and offnot to be confused with the speed at which light propagates, which is determined by the properties of the medium and has an upper limit, particularly its index of. Energy scaling of modelocked fiber lasers with chirally. This configuration is suitable for power scaling in which many pump sources are used around the periphery of the coil. The availability of this kind of source may lead to a paradigm change in ultrashort pulse laser surgery of the eye as regards the laser wavelengths used.
Fiber laser sources offer excellent beam quality, maintenance free operation, reliability and stability. The first is continuous wave or systems with long pulse widths of a microsecond or more. Scaling of p av andor t res would provide the scaling of ultrashort pulse energy on condition that a stable ultrashort pulse emerges spontaneously socalled, modelocking selfstart condition in a laser system. The final ambition of the caps project is the introduction of usp laser systems in large scale production processes with high throughput. We report on two pulse compressors for a highpower thin disk laser oscillator using rodtype fiber amplifiers. Power scaling of dispersionmanaged erdoped ultrashort. Industrial femtosecond lasers and material processing. Pulses from a single modelocked laser are distributed to a number of spatially separated fiber amplifiers and coherently combined after amplification. Ultrashort laser pulse phenomena, third edition optics and photonics series currently unavailable. These properties result in compact, singlepass and even monolithic ultrashortpulse laser systems, which are capable of emitting average powers up to the kilowatt level. We have seen that the concept of power scaling in a meaningful sense must be based on a welldefined and repeatable scaling procedure. Thuliumdoped fibers with very large modefield areas offer new opportunities for the power scaling of midir ultrashort pulse laser sources. Aqwest designs and integrates highaverage power, highenergy ultrashort pulse laser for military and civilian applications. Two approaches are discussed, the amplification of linearly chirped parabolic pulses and a fiber based chirped pulse amplification system.
Both systems are seeded by a standard sesam modelocked thin disk laser that delivers 16 w of average power at a repetition rate of 10. One of the first coherent, tutorial graduate level textreference books on ultrashort laser phenomena, this book presents an introduction to the phenomena and explains how it can be used to help examine problems in areas such as electromagnetism. The second system considered again uses a large mode amplifier, operating at 1550nm using eryb codoped fiber. While continouswave cw laser systems drive to more efficiency, compactness and robustness, ultra short pulse usp solidstate lasers ssl gain increasing attention from industry due to their high average power levels, increasing pulse energies and more flexible repetition rates. Low dispersion high power optical fiber amplifier for. Next, the advance of fiber laser amplifiers to obtain the high power ultrashort pulse is described in sect.
Pulse fiber laser series lasersmart laser fiber laser. In such lasers, the pump is not confined within the cladding of the fiber, but instead pump light is delivered across the core multiple times because it is coiled in on itself. This book is divided into six main sections dealing with short and ultrashort laser pulses, laserproduced soft xray sources, largescale highpower laser systems, free electron lasers, fiberbased sources of short optical pulse, and applications of short pulse lasers. As will be shown, these conditions are highly nontrivial for energyscalable lasers and can limit substantially the pulse energy. Ultrashort pulse lasers lasers for industry fiber lasers. Feb 14, 2011 to summarize, we have demonstrated the energy scaling of modelocked fiber lasers by use of a chirallycoupled core fiber. The passive modelocking technique of polarization additive pulse modelocking papm is. Unlike conventional ultrashort pulse bulk solidstate laser systems, ultrafast fiber amplifiers can be scaled to average powers 100 w without significant beamquality distortion from thermal lensing. Ultrashort pulse fiber lasers and their applications iopscience.
Ultrashortpulse laser eye surgery uses fiber technology. Coronado optical fiber amplifier in addition to our standard edfa systems, calmar lasers low dispersion high power edfa amplifier is specially designed for ultrashort pulse amplification. The dispersion compensating edfa ampld, also described as high speed, short pulse edfa due to its spe. An ultrashort pulse laser is a laser that emits ultrashort pulses of light, generally of the order of femtoseconds to ten picoseconds.
Jul 21, 2011 passive modelocking in fiber lasers is investigated by numerical and experimental means. Fiber laser systems offer unique properties for the amplification of ultrashort pulses to high powers. The team here at advanced optowave have years of combined experience in this space and can help you determine the right ultrashort pulse laser for your application. Peak power on the rise features oct 2017 photonics. The pump light is launched into an inner cladding rather than into the much smaller fiber core, in which the laser light is generated. The average laser powers of the short and ultrashort pulse lasers from trumpf range from just a few watts to several hundred watts. Aqwest system uses a highperformance epdlbased amplifier fed by a commercially available seed laser to generate and launch ultrashort pulses in the kilowatt average power range. The utilized zigzag type slab lasers showed some advantages in principle, but the technical realization was not. While laser systems with slab shaped crystals are well known since very long time, those systems did not make their way to industrial high power products. Several new directions for ultrafast fiber lasers invited. The pulse width typically ranges from picoseconds down to few femtoseconds in duration. One of the most successful types is the so called photonic crystal fiber featuring microstructured waveguides. All fiber similariton ultrashort pulse laser systems at erbiumdoped wavelengthband.
The existing market for ultrafast lasers remains dominated by solidstate lasers, primarily ti. We report on two pulse compressors for a high power thin disk laser oscillator using rodtype fiber amplifiers. The used concept, involving function calls rather than commands for sending the pulse through various optical components, turns out to be extremely. Besides the actual high power laser development, this group focuses on the technologies for distribution, conversion, simulation, and measurement of the ultrashort pulses. Fiber laser, oscillator, amplifier, all fiber structure, high power lasers, materials. Thuliumdoped fibers with ultra large modefield areas offer new opportunities for the power scaling of midir ultrashort pulse laser sources. But also in terms of the available pulse energies and peakpowers, stateoftheart fiber lasers have become competitive to other solidstate laser concepts. Fiber lasers, which consist of ideal waveguides of optical fibers, work as stable, practical, and maintenance free lasers.
685 1544 1599 1537 987 683 546 81 476 1246 1578 888 839 976 1163 302 269 475 869 16 1071 1033 1235 1023 1265 139 215 876 200 150 1398 1093 1312 825 577 1142 1335 413 799 87 408 1234 1086 955 1070 209 510 1482 950