Showing papers on "Chirped pulse amplification published in 1995"
Patent•
19 May 1995
TL;DR: Cladding-pumped fibers are used for chirped pulse amplification of ultrashort optical pulses, increasing the average output power by one order of magnitude and substantially decreasing the cost of pump sources as discussed by the authors.
Abstract: Cladding-pumped fibers are used for chirped pulse amplification of ultrashort optical pulses, increasing the average output power by one order of magnitude and substantially decreasing the cost of pump sources. Broad-area multimode diode pumped Er/Yb codoped fiber amplifiers and MOPA pumped high-power Er-doped fiber amplifiers are used to achieve chirped pulse amplification.
139 citations
TL;DR: In this article, a chirped Bragg gratings are used as stretchers and compressors for distortionless amplification of femtosecond pulses in chirping pulse amplification system.
Abstract: In‐fiber chirped Bragg gratings are used as stretchers and compressors for distortionless amplification of femtosecond pulses in chirped pulse amplification system. It is shown that using opposite directions of pulse propagation the effects of higher order dispersion and grating irregularities can be eliminated and the original pulse shape and duration can be recovered. Using these gratings a compact all‐fiber system consisting of a mode‐locked fiber oscillator and an erbium‐doped fiber amplifier was built. 330 fs bandwidth‐limited pulses from a fiber oscillator were stretched to 30 ps, amplified and recompressed back to 408 fs. The maximum energy of the pulses after the amplifier was 6 nJ and was at the threshold of nonlinear effects for a 30 ps stretched pulse.
110 citations
Patent•
10 May 1995TL;DR: In this article, a method and apparatus for generating high pulse energy, short optical pulses having relatively high contrast is presented. But the system is not locked to a fixed repetition rate as it is controlled by an electronic trigger.
Abstract: The invention provides a method and apparatus for generating high pulse energy, short optical pulses having relatively high contrast. The system comprises a diode laser to seed a compact diode pumped amplifier, and comprises pulse shaping and cleaning elements to achieve relatively high energies and high contrast. The system is not locked to a fixed repetition rate as it is controlled by an electronic trigger. The system of the invention comprises a selectively triggered pulse source (asynchronous) which is coupled to pulse amplifying/pulse shaping means, which is coupled to pulse cleaning means, which is further coupled to a chirped pulse amplification (CPA) system. The method of the invention comprises the general steps of: (1) selectively triggering a pulse source; (2) amplifying the pulse and shaping it; (3) increasing contrast of the pulse utilizing a preferred, passive, nonlinear pulse cleaner; and (4) increasing the energy of the pulse and decreasing its pulse width by chirped pulse amplification (CPA) means. In the method of the invention, steps (2) and (3) may be repeated in order to achieve a desired energy intensity and contrast.
74 citations
TL;DR: In this article, a method for compensating large amounts of second-and third-order material dispersion is described, and two simple, compact and robust stretcher-compressor systems for microjoule and millijoule-level chirped-pulse amplification are presented.
Abstract: We describe a method for compensating large amounts of second- and third-order material dispersion, and we present two simple, compact and robust stretcher-compressor systems for microjoule-and millijoule-level chirped-pulse amplification. These systems, which use dispersive material to stretch and a modified grating pair to compress the pulse, provide expansion and compression with full cubic-phase compensation. Unlike previous fiber-stretcher systems which were limited to picosecond pulse durations, these systems can be used effectively with 50-fs microjoule pulses or 100-fs millijoule pulses. The results of our model are described, including the quartic-phase limitations for both systems. We discuss other applications of this grating pair to other areas of ultrafast optics, including intracavity dispersion compensation for femtosecond oscillators. >
70 citations
Proceedings Article•
21 May 1995TL;DR: In this paper, the limitations introduced during the amplification of such short pulses can be found by studying the spectral properties of Ti:sapphire amplifiers, which can be used to obtain a few tens of millijoules.
Abstract: Pulses with durations shorter than 10 fs have been produced in several laboratories by using Ti:sapphire oscillators. Chirped pulse amplification (CPA) can be used to amplify such pulses to energies of a few tens of millijoules.1 The limitations introduced during the amplification of such short pulses can be found by studying the spectral properties of Ti:sapphire amplifiers.
52 citations
TL;DR: In this article, a TEM/sub 00/Ti:sapphire regenerative amplifier exhibiting a net gain of 10/sup 9/ (from 10 pJ to 9 mJ) at 1053 nm with extremely stable energy output (/spl plusmn/3%).
Abstract: Chirped-pulse amplification in Ti:sapphire in the low-gain region above /spl mu/m is described. Direct measurement of the stimulated emission cross section shows that the value is nearly 50% lower in this region than previously reported based on extrapolation from fluorescence data at shorter wavelengths. We have developed a TEM/sub 00/ Ti:sapphire regenerative amplifier exhibiting a net gain of 10/sup 9/ (from 10 pJ to 9 mJ) at 1053 nm with extremely stable energy output (/spl plusmn/3%). Further amplification in a ring amplifier produces in excess of 60 mJ at a 10 Hz repetition rate. The performance of these amplifiers is compared with a theoretical model which includes whole-beam self-focusing, mode-size variation due to a radial gain profile, and spectra-temporal saturation. >
46 citations
TL;DR: Continuous tuning of the cubic and quartic phases of the pulse stretcher in a chirped-pulse amplification laser system is demonstrated and near-bandwidth-limited recompression of 100-fs pulses is obtained by minimizing the total phase through fourth order.
Abstract: We demonstrate continuous tuning of the cubic and quartic phases of the pulse stretcher in a chirped-pulse amplification laser system. We obtain near-bandwidth-limited recompression of 100-fs pulses by minimizing the total phase through fourth order.
36 citations
TL;DR: In this article, a totally integrated all-fibre femtosecond chirped pulse amplification scheme was described, which was temporally stretched, amplified in a diode pumped Yb-Er fiber amplifier and recompressed to give 900 fs pulses of 1.6 nJ energy and an average power of 4.8 mW.
Abstract: A totally integrated all-fibre femtosecond chirped pulse amplification scheme is described. Transform-limited 670 fs pulses at a 3.1 MHz repetition rate, derived from a diode pumped Yb-Er figure-of-eight fibre laser, were temporally stretched, amplified in a diode pumped Yb-Er fibre amplifier and recompressed to give 900 fs pulses of 1.6 nJ energy and an average power of 4.8 mW. Chirped Bragg fibre gratings were used to stretch and recompress the pulses, in a novel configuration which minimises loss.
35 citations
TL;DR: Experimental results of the amplification of strongly amplitude-modulated chirped pulses resulting from the coherent addition of two delayed short pulses show that the prepulses and postpulses are blue shifted and red shifted, respectively, explaining the causality of the system.
Abstract: We present experimental results of the amplification of strongly amplitude-modulated chirped pulses resulting from the coherent addition of two delayed short pulses. The nonlinearities in the amplifier chain induce a temporal diffraction resulting in prepulses and postpulses, in addition to the two main pulses when compressed. Simultaneously, temporal-resolved and spectral-resolved output pulses show that the prepulses and postpulses are blue shifted and red shifted, respectively, explaining the causality of the system.
33 citations
TL;DR: In this article, background-free intensity autocorrelation studies of sub-50 fs pulses from a Kerr lens mode-locked (KLM) Ti: sapphire laser over an intensity dynamic range of approximately 7 orders of magnitude.
25 citations
TL;DR: In this article, the design of a Cr:LiSAF laser system capable of generating ultrashort, 90-fs Fourier-transform limited pulses with a peak power of 8 TW was discussed.
Abstract: We discuss the design of a Cr:LiSAF laser system capable of generating ultrashort, 90-fs Fourier-transform limited pulses with a peak power of 8 TW. Using chirped pulse amplification and flashlamp-pumped Cr:LiSAF amplifiers this system incorporates a regenerative amplifier and three additional double-pass amplifiers with increasing aperture up to 25 mm. The temporal performance as well as the spatial beam quality are discussed in detail. We discuss extension of this system to the Petawatt power level. >
TL;DR: Microjoule pulse energies are achieved from a single-stage upconversion fiber amplifier for the first time, to the authors' knowledge, in this demonstration of chirped-pulse amplification with a multimode Tm:ZBLAN fiber.
Abstract: Microjoule pulse energies are achieved from a single-stage upconversion fiber amplifier for the first time, to our knowledge, in this demonstration of chirped-pulse amplification with a multimode Tm:ZBLAN fiber. A Ti:sapphire laser system provides the seed pulse for the fiber upconversion amplifier that produces picosecond pulse trains with energies as great as 16 μJ at a repetition rate of 4.4 kHz.
TL;DR: In this article, a pulse stretching-compression system suitable for kHz-rate chirped-pulse amplification of ≈10 fs pulses in Ti:sapphire systems is demonstrated.
10 Apr 1995
TL;DR: In this paper, the first all-fiber chirped-pulse amplification circuit was demonstrated. Butts et al. used in-fibers Bragg gratings to replace conventional diffraction-grating compressors and stretchers.
Abstract: Compact sources of high energy ultrashort pulses are described. Femtosecond and picosecond optical pulses with microjoule energies are obtained using chirped-pulse fiber amplifiers. Mode-locked fiber lasers and fast-tuned laser diodes are used to generate initial pulses for amplification. Efficient frequency conversion of amplified pulses is demonstrated and microjoule second-harmonic pulses are produced. The first all-fiber chirped pulse amplification circuit is demonstrated. It uses in-fiber chirped Bragg gratings, which replaces conventional diffraction-grating compressors and stretchers.
08 Dec 1995
TL;DR: In this article, the authors have developed designs for high efficiency reflection gratings that use only transparent dielectric materials to avoid the inevitable light absorption that accompanies conductivity, and they report their present understanding of short-pulse laser induced damage.
Abstract: Chirped pulse amplification is increasingly used to produce intense ultrashort laser pulses. When high-efficiency gratings are the dispersive element, as in the LLNL Petawatt laser, their susceptibility to laser induced damage constitutes a limitation on the peak intensities that can be reached. To obtain robust gratings, it is necessary to understand the causes of short-pulse damage, and to recognize the range of design options for high efficiency gratings. Metal gratings owe their high efficiency to their high conductivity. To avoid the inevitable light absorption that accompanies conductivity, we have developed designs for high efficiency reflection gratings that use only transparent dielectric materials. These combine the reflectivity of a multilayer dielectric stack with a diffraction grating. We report here our present understanding of short-pulse laser induced damage, as it applies to dielectric gratings.
01 Feb 1995-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, the authors describe the laser requirements, including pulse duration, intensity, energy, and wavelength, for a collider with an interaction point near the interaction point of an e+ e− or e− e− collider.
Abstract: Compton backscattering of laser photons near the interaction point of an e+ e− or e− e− collider can be used to produce a γ-γ or γ-e− collider. This paper describes the laser requirements, including pulse duration, intensity, energy, and wavelength, for such a collider. For most of the proposed, next generation, e+ e− colliders, the laser wavelength should be in the near-infrared, with a pulse duration of 1 ps or less and an energy of ∼ 1 J per pulse. Current chirped pulse amplification laser systems in solid state lasing materials are well suited to meet these requirements. These systems are described.
TL;DR: A review of state-of-the-art laser systems for high power and intensity using as illustrations chirped pulse amplification (CPA) operation of the infrared Nd glass laser (Vulcan) and both CPA and Raman laser operations of the ultraviolet KrF laser (Sprite) at the Rutherford Appleton Laboratory in the UK can be found in this article.
Abstract: Experiments with focused intensity of laser light exceeding 1019 Wcm−2 have recently become possible through exploitation of new laser techniques and materials. The rate of advance is rapid and petawatt (1015 W) power with focused intensity upto 1021 Wcm−2 is only a year or two away. — In this review I will summarise the main features of state of the art lasers designed for high power and intensity using as illustrations chirped pulse amplification (CPA) operation of the infrared Nd glass laser (Vulcan) and both CPA and Raman laser operation of the ultraviolet KrF laser (Sprite) at the Rutherford Appleton Laboratory in the UK. These laser systems delivering upto 1019 Wcm−2 in focused beams, are enabling research investigations at the highest intensities currently available. — I will present also highlights of current research using these lasers in the fields of XUV harmonic generation, X-ray laser development and studies underlying a new concept of fast ignition of thermonuclear fusion.
11 Apr 1995-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: This work shows that the techniques of high gain harmonic generation and chirped pulse amplification (CPA) can be combined to generate deep-uv radiation with peak power of order of 100 GW and pulse width of 5 fs.
Abstract: In this work we show that the techniques of high gain harmonic generation and chirped pulse amplification (CPA) can be combined to generate deep-uv radiation with peak power of order of 100 GW and pulse width of 5 fs. The resulting pulse would have wide range of applications.
Journal Article•
TL;DR: In this article, high quality seed pulses from mirror-dispersion-controlled Ti:sapphire system allow chirped pulse amplification without a pulse stretcher, without the need for a pulse ambulance.
Abstract: High-quality seed pulses from mirror-dispersion-controlled Ti:sapphire system allow chirped pulse amplification without a pulse stretcher.
10 Apr 1995
TL;DR: In this paper, a Tm:ZBLAN upconversion fiber amplifier was used for chirped pulse amplification using a Ti:sapphire laser system, which produces subpicosecond pulse trains with energies as great as 16 (mu) J at repetition rate of 4.4 kHz.
Abstract: Microjoule pulse energies are achieved from a single stage upconversion fiber amplifier for the first time in this demonstration of chirped pulse amplification using a multimode Tm:ZBLAN fiber. A Ti:sapphire laser system provides the seed pulse for the upconversion fiber amplifier which produces subpicosecond pulse trains with energies as great as 16 (mu) J at repetition rate of 4.4 kHz. The compressed pulse peak power is more than 1 MW, and the pulse is characterized both temporally and spatially.
14 Jul 1995
TL;DR: In this paper, a Ti:sapphire chirped pulse amplification system was used in a wide band gap materials such as SiO2 and MgF2 for single-shot laser induced breakdown.
Abstract: Single-shot laser induced breakdown, in wide band gap materials such as SiO2 and MgF2, has been studied over almost 5 orders of magnitude in duration from 150 fs to 7 ns. A Ti:sapphire chirped pulse amplification system was used in this experiement, so the pulse duration could be continuously adjusted without changing any other parameters. The damage threshold was detected by looking at the plasma formation and the change of material transmission coefficient. The avalanche mechanism was found to dominate over the entire pulse-width range even for 150 fs pulses where we would expect multi-photon processes to take over. A strong departure from the conventional fluence threshold scaling law is observed for pulses shorter than 10 ps, where beyond this point the fluence threshold increases. Also, it is observed for the first time that for short pulses the damage threshold becomes very accurate and less statistical than that for longer pulses.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
TL;DR: In this article, the design and performance of a double-side pumped Ti:sapphire regenerative amplifier operating at 1.053 mu m wavelength is presented, used as a pre-amplifier in a terawatt VULCAN laser system based on chirped pulse amplification to amplify stretched femtosecond pulses to millijoule levels at 10 Hz repetition rates with an excellent stability.
Abstract: The design and performance of a reliable double-side pumped Ti:sapphire regenerative amplifier operating at 1.053 mu m wavelength is presented. The device is used as a pre-amplifier in a terawatt VULCAN laser system based on chirped pulse amplification to amplify stretched femtosecond pulses to millijoule levels at 10 Hz repetition rates with an excellent stability.
25 Sep 1995
TL;DR: The SDL accelerator system as mentioned in this paper consists of a high brightness short pulse linac, a station for coherent synchrotron and transition radiation experiments, a short bunch storage ring, and an ultra-violet free electron laser utilizing the NISUS wiggler.
Abstract: The National Synchrotron Light Source (NSLS) has initiated an ambitious project to develop fourth generation radiation sources. To achieve this goal, the Source Development Laboratory (SDL) builds on the experience gained at the NSLS, and at the highly successful BNL Accelerator Test Facility. The SDL accelerator system will consist of a high brightness short pulse linac, a station for coherent synchrotron and transition radiation experiments, a short bunch storage ring, and an ultra-violet free electron laser utilizing the NISUS wiggler. The electrons will be provided by a laser photocathode gun feeding a 210 MeV S-band electron linac, with magnetic bunch compression at 80 MeV. Electron bunches as short as 100 {mu}m with 1 nC charge will be used for pump-probe experiments utilizing coherent transition radiation. Beam will also be injected into a compact storage ring which will be a source of millimeter wave coherent synchrotron radiation. The linac will also serve as the driver for an FEL designed to allow the study of various aspects of single pass amplifiers. The first FEL configuration will be as a self-amplified spontaneous emission (SASE) FEL at 900 nm. Seeded beam and sub-harmonic seeded beam operations will push the output wavelength below 200 nm. Chirped pulse amplification (CPA) operation will also be possible, and a planned energy upgrade (by powering a fifth linac section) to 310 MeV will extend the wavelength range of the FEL to below 100 nm.
Proceedings Article•
21 May 1995
10 Apr 1995
TL;DR: In this article, a chirped pulse amplification system capable of producing femtosecond pulses with energy above one joule was developed, using a large aperture, flashlamp pumped Cr-LiSrAlF{sub 6} (Cr:LiSAF) amplifier.
Abstract: The authors have developed a chirped pulse amplification system capable of producing femtosecond pulses with energy above one joule. This is accomplished by using a large aperture, flashlamp pumped Cr-LiSrAlF{sub 6} (Cr:LiSAF) amplifier. Optimum design of the 19 mm diameter amplifier results in a single pass gain of 5 with good beam quality. This amplifier produces 1.05 J pulses after compression with a width of < 125 fs at a repetition rate of 0.05 Hz.
08 Dec 1995
TL;DR: The VULCAN as discussed by the authors is a multi-beam, multi-terawatt laser facility based on Nd:glass operating at 1053 nm, providing four experimental areas with laser radiation at a range of pulse durations from 700 fs to 20 ns, at fundamental frequency, frequency doubled, or, as a limited option, frequency tripled wavelengths.
Abstract: VULCAN is a multi-beam, multi-terawatt laser facility based on Nd:glass operating at 1053 nm. The system is highly versatile, supplying four experimental areas with laser radiation at a range of pulse durations from 700 fs to 20 ns, at fundamental frequency, frequency doubled, or, as a limited option, frequency tripled wavelengths. Beams are available in a number of geometries dictated by the university based programs, which at present include: cluster; line focus including x-ray laser oscillator/amplifier geometry; backlighting; probing; and chirped pulse amplification (CPA) configurations. The system has eight beams which can deliver synchronized long and short pulses including two beams which can deliver subpicosecond CPA pulses. The CPA capabilities on VULCAN are an integral part of the laser system, not only delivering sub-picosecond pulses, but allowing uncompressed pulses and multi-pulses to be delivered to the target areas synchronized with the nanosecond pulses. This paper describes the system configuration, details the means of pulse synchronization and presents some of the pulse manipulation techniques used on VULCAN to provide the laser requirements for the experimental program.
Proceedings Article•
21 May 1995
TL;DR: The main benefit of chirped pulse amplification is that very-high-peak power lasers have become laboratory tools as discussed by the authors, and the emphasis in this area has continued to be higher peak power in a more compact form.
Abstract: The main benefit of chirped pulse amplification is that very-high-peak power lasers have become laboratory tools. The emphasis in this area has continued to be higher peak power in a more compact form. One major improvement has been the use of tunable solid-state materials for amplifying shorter pulses which was first demonstrated in flashlamp-pumped alexandrite.1 Another decrease in size and improvement in stability has been achieved by going to laser pumping which was first demonstrated in Ti:sapphire pumped by frequency-doubled Nd:YAG.2 Further dramatic improvement in peak power has recently been accomplished by amplifying shorter pulses in this type of system.3
10 Apr 1995
TL;DR: In this article, a simple method for compensating large amounts of second and third-order material dispersion is described, and two compact and robust stretcher-compressor systems for microjoule and millijoule-level chirped pulse-amplification are presented.
Abstract: We describe a simple method for compensating large amounts of second- and third-order material dispersion, and we present two compact and robust stretcher-compressor systems for microjoule-and millijoule-level chirped pulse-amplification.
01 Jan 1995
TL;DR: In this article, the collector and emitter contacts are alloyed AuGe/Ni/Au. The base region is exposed by dry etching and contact is made with F”Au metal.
Abstract: to be fabricated later in the process. The subcollector is isolated by an He+ ion implant. The base region is exposed by dry etching and contact is made with F”Au metal. The collector and emitter contacts are alloyed AuGe/Ni/Au. The technology employs a three-level metal scheme, which also includes NiCr resistors and MIM capacitors. Circuit fabrication was performed by standard optical lithography using a modified I-line GCA
TL;DR: In this article, the pedestal reduction of high-intensity ultrashort laser pulses generated by chirped pulse amplification was analyzed and it was shown that a contrast ratio exceeding 1010 is achievable with appropriate filtering techniques.
Abstract: We present numerical calculations on pedestal reduction of high-intensity ultrashort laser pulses generated by chirped pulse amplification. When an optical fiber is used as a pulse expander to generate a chirped pulse, spectral filtering is not effective in reducing the pedestal arising from the nonlinear chirp near the central frequency. The temporal filtering, in contrast, is effective in reducing the pedestals arising from various chirp nonlinearities and amplified spontaneous emission. It is shown that a contrast ratio exceeding 1010 is achievable with appropriate filtering techniques.