Showing papers on "Chirped pulse amplification published in 2011"
TL;DR: A fiber chirped- pulse amplification system capable of generating nearly transform-limited sub 500 fs pulses with 2.2 mJ pulse energy at 11 W average power and a record peak power of 3.8 GW could be achieved by combining active phase shaping with an efficient reduction of the acquired nonlinear phase.
Abstract: We report on the experimental demonstration of a fiber chirped- pulse amplification system capable of generating nearly transform-limited sub 500 fs pulses with 22 mJ pulse energy at 11 W average power The resulting record peak power of 38 GW could be achieved by combining active phase shaping with an efficient reduction of the acquired nonlinear phase Therefore, we used an Ytterbium-doped large-pitch fiber with a mode field diameter of 105 µm as the main amplifier
244 citations
TL;DR: Measurements show that the contrast ratio of the main laser pulse is around 10(10) within the time scale of -400 ps and the duration of compressed pulse is 27.9 fs, corresponding to a peak power of 1.16 PW.
Abstract: Based on a combined scheme of doubled chirped-pulse amplification and a femtosecond noncollinear optical-parametric amplifier, a high-contrast femtosecond laser pulse with energy of up to 32.3 J has been generated by improving the gain efficiency and boosting the pump energy to 120 J in the final amplifier. Our measurements show that the contrast ratio of the main laser pulse is around 1010 within the time scale of −400 ps and the duration of compressed pulse is 27.9 fs, corresponding to a peak power of 1.16 PW.
110 citations
TL;DR: An all-optical and passively carrier-to-envelope-phase-stabilized (CEP-st stabilized) optical parametric chirped pulse amplification (OPCPA) system is demonstrated with sub-250-mrad CEP stability over 11 min and better than 100 mrad over 11 s.
Abstract: An all-optical and passively carrier-to-envelope-phase-stabilized (CEP-stabilized) optical parametric chirped pulse amplification (OPCPA) system is demonstrated with sub-250-mrad CEP stability over 11 min and better than 100 mrad over 11 s. This is achieved without any electronic CEP stabilization loop for 160 kHz pulse repetition rate in the few cycle regime.
85 citations
TL;DR: A Yb:YAG Innoslab laser amplifier system for generation of subpicsecond high energy pump pulses for optical parametric chirped pulse amplification (OPCPA) at high repetition rates and the possibility to use subpicosecond pulses to derive a stable continuum in a YAG crystal for OPCPA seeding is investigated.
Abstract: We report on a Yb:YAG Innoslab laser amplifier system for generation of subpicsecond high energy pump pulses for optical parametric chirped pulse amplification (OPCPA) at high repetition rates. Pulse energies of up to 20 mJ (at 12.5 kHz) and repetition rates of up to 100 kHz were attained with pulse durations of 830 fs and average power in excess of 200 W. We further investigate the possibility to use subpicosecond pulses to derive a stable continuum in a YAG crystal for OPCPA seeding.
85 citations
TL;DR: This CPA system based on diode-pumped Yb:YAG is optically synchronized with a broadband seed laser and therefore ideally suited for pumping optical parametric chirped pulse amplification stages on a ps-timescale.
Abstract: We present a chirped pulse amplification (CPA) system based on diode-pumped Yb:YAG. The stretched ns-pulses are amplified and have been compressed to less than 900fs with an energy of 200mJ and a repetition rate of 10Hz. This system is optically synchronized with a broadband seed laser and therefore ideally suited for pumping optical parametric chirped pulse amplification (OPCPA) stages on a ps-timescale.
57 citations
TL;DR: Simulations show up to 60% energy transfer from pump pulse to probe pulse, implying that multikilojoule ultraviolet petawatt laser pulses can be produced using this scheme, which has important consequences for the demonstration of fast-ignition inertial confinement fusion.
Abstract: Raman amplification in plasma has been promoted as a means of compressing picosecond optical laser pulses to femtosecond duration to explore the intensity frontier. Here we show for the first time that it can be used, with equal success, to compress laser pulses from nanosecond to picosecond duration. Simulations show up to 60% energy transfer from pump pulse to probe pulse, implying that multikilojoule ultraviolet petawatt laser pulses can be produced using this scheme. This has important consequences for the demonstration of fast-ignition inertial confinement fusion.
53 citations
TL;DR: In this article, the authors reported dissipative solitons generation in the figure-8 all-normal dispersion fiber ring laser with the use of NOLM together with polarization controllers.
Abstract: We report dissipative solitons generation in the figure-8 all-normal dispersion fiber ring laser. The steep edge of the output optical spectrum results from the filtering effect of NOLM together with polarization controllers (PCs). No any physical bandpass filters are used in the cavity. Moreover, the output wavelength can be tuned in a wide range of about 20 nm. In the long-wavelength region, the spectral filtering effect of NOLM becomes weaker and output spectrum shows only one steep side. Filtering effect can perform periodically with increasing the pump power. The highly chirped pulse has good potential for application to the chirped pulse amplification (CPA) system.
50 citations
TL;DR: For the first time, to the authors' knowledge, more than 100 W of average power are transmitted through a noble-gas-filled hollow fiber.
Abstract: We report on nonlinear pulse compression at very high average power. A high-power fiber chirped pulse amplification system based on a novel large pitch photonic crystal fiber delivers 700 fs pulses with 200 μJ pulse energy at a 1 MHz repetition rate, resulting in 200 W of average power. Subsequent spectral broadening in a xenon-filled hollow-core fiber and pulse compression with chirped mirrors is employed for pulse shortening and peak power enhancement. For the first time, to our knowledge, more than 100 W of average power are transmitted through a noble-gas-filled hollow fiber. After pulse compression of 81 fs, 93 μJ pulses are obtained at a 1 MHz repetition rate.
49 citations
TL;DR: A versatile tunable and highly stable ultrabroadband Ti:sapphire chirped pulse amplification system with unique wavelength tunability capabilities expanded into the UV and deep-UV by second and third harmonic generation with excellent energy stability.
Abstract: We demonstrate a versatile tunable and highly stable ultrabroadband Ti:sapphire chirped pulse amplification system with a compressed pulse energy of 20 mJ at 100 Hz repetition rate. High power Ti:Sa systems in principle do not offer wavelength tunability due to gain narrowing. Here we demonstrate transform limited pulse generation from 15 fs to 94 fs with tunable central wavelength (λc from 755 nm to 845 nm) and bandwidth (130nm<Δλ<16 nm) as well as multi-color, time synchronized, sub-100 fs pulses with user defined central wavelength separation. The unique wavelength tunability capabilities have been expanded into the UV and deep-UV by second and third harmonic generation with excellent energy stability. Enhanced energy stability is achieved by multiplexing six ultrastable diode-based solid state pump lasers.
48 citations
TL;DR: An all-diode-pumped Yb:YAG chirped pulse amplification laser that produces 100 mJ pulses of 5 ps duration at 100 Hz repetition rate and the optical efficiency of this amplifier is higher than that of other diode- pumped systems of comparable energy.
Abstract: We have demonstrated an all-diode-pumped Yb:YAG chirped pulse amplification laser that produces 100 mJ pulses of 5 ps duration at 100 Hz repetition rate. The compact laser system combines a room-temperature Yb:YAG regenerative amplifier for increased bandwidth and a cryogenically cooled Yb:YAG four-pass amplifier for improved heat dissipation and increased efficiency. The optical efficiency of this amplifier is higher than that of other diode-pumped systems of comparable energy.
48 citations
TL;DR: Using a model for the nonlinear dynamics consistent with quantum mechanics, the evolution of excess noise in an OPCPA is studied to explain the macroscopic characteristics seen previously in experiments in the practically important saturation regime.
Abstract: Noise evolution in an optical parametric chirped-pulse amplifier (OPCPA) differs essentially from that of an optical parametric or a conventional laser amplifier, in that an incoherent pedestal is produced by superfluorescence that can overwhelm the signal under strong saturation. Using a model for the nonlinear dynamics consistent with quantum mechanics, we numerically study the evolution of excess noise in an OPCPA. The observed dynamics explain the macroscopic characteristics seen previously in experiments in the practically important saturation regime.
Journal Article•
TL;DR: In this article, an overview of the design of a 10 GeV laser plasma accelerator (LPA) that will be driven by a PW-class laser system and of the BELLA Project is presented.
Abstract: An overview is presented of the design of a 10 GeV laser plasma accelerator (LPA) that will be driven by a PW-class laser system and of the BELLA Project, which has as its primary goal to build and install the required Ti:sapphire laser system for the acceleration experiments. The basic design of the 10 GeV stage aims at operation in the quasi-linear regime, where the laser excited wakes are largely sinusoidal and offer the possibility of accelerating both electrons and positrons. Simulations show that a 10 GeV electron beam can be generated in a meter scale plasma channel guided LPA operating at a density of about 1017 cm-3 and powered by laser pulses containing 30-40 J of energy in a 50- 200 fs duration pulse, focused to a spotsize of 50-100 micron. The lay-out of the facility and laser system will be presented as well as the progress on building the facility.
TL;DR: In this article, the authors developed a theory of optimization of amplifier bandwidth and conversion efficiency in ultrabroadband optical parametric chirped pulse amplification based on the principle of making the optimal conversion length uniform in time through pulse shaping.
Abstract: We developed a theory of optimization of amplifier bandwidth and conversion efficiency in ultrabroadband optical parametric chirped pulse amplification based on the principle of making the optimal conversion length uniform in time through pulse shaping. Conformal profiles, ideal combinations of pump intensity, seed intensity, and wave-vector mismatch temporal profiles can be found analytically by use of the exact Jacobi elliptic function solutions for signal gain and pump depletion in optical parametric amplification. We derive and investigate these gain equations for the general purpose of aiding the design of optical parametric amplifiers. Using these analytics, through an extensive analysis of conformal profile methods, we find conformal profile pulse shaping can significantly boost amplifier bandwidth as well as conversion efficiency, allowing in some amplifiers a severalfold increase in obtainable peak power. Pump pulse shaping is found to be particularly effective and flexible.
TL;DR: A high-energy fiber chirped-pulse amplification system operating at 1 mJ pulse energy and nearly transform-limited pulses is used to achieve ultrabroadband amplification in two 2mm beta-barium borate crystals.
Abstract: An optical parametric chirped-pulse amplification system delivering pulses with more than 12GW peak power is presented. Compression to sub-5fs, 87μJ and 5.4fs, 100μJ is realized at the 30kHz repetition rate. A high-energy fiber chirped-pulse amplification system operating at 1mJ pulse energy and nearly transform-limited pulses is used to achieve ultrabroadband amplification in two 2mm beta-barium borate crystals. Precise pulse shaping is used to compress the pulses to a few percentages of their transform limit. Assuming diffraction limited focusing (d<2μm), peak intensities as high as 1018W/cm2 can be reached.
TL;DR: In this article, a 3D two-temperature model is introduced to investigate femtosecond ablation on aluminum film and 3D temperature evolutions for both electrons and lattice are obtained.
Abstract: In this paper, a 3D two-temperature model is introduced to investigate femtosecond ablation on aluminum film. 3D temperature evolutions for both electrons and lattice are obtained, which present us a vivid view of the energy transformation process during femtosecond ablation. Simulated 3D ablation craters irradiated by a single pulse with different energy are acquired, from which we can easily and precisely predict crater depth and radius before ablation takes place. In the experiment we measure the radii of the craters ablated by pulses with different energy and numbers delivered from a chirped pulse amplification Ti: sapphire system. The threshold fluence for both single and multi pulses are obtained. Comparisons are made between results of the experiment and relative simulated calculations show the reliability of our proposed calculation model.
TL;DR: The cw and femtosecond laser operations of Yb(3+):CaYAlO(4) (Yb:CYA) are demonstrated and the η(slope) and η (opt) of the mode-locked laser were 37% and 20%, respectively.
Abstract: The cw and femtosecond laser operations of Yb(3+):CaYAlO(4) (Yb:CYA) are demonstrated. The laser emitted a maximum cw power of 1.94 W with a slope efficiency (η(slope)) of 71% and an optical-to-optical efficiency (η(opt)) of 51%. Under mode-locking operation, the laser emitted near transform-limited pulses with 156 fs pulse width, 8.1 nJ pulse energy and 0.74 W average power. The η(slope) and η(opt) of the mode-locked laser were 37% and 20%, respectively.
TL;DR: In this paper, a photonic quasi-crystal fiber (PQF) was proposed to achieve the desired high normal group velocity dispersion (GVD) of 1000 ps2/km at 1.06 μm and inner core effective mode area as 35 μm2.
Abstract: We propose a fiber stretcher for stretching the high-energy ultrashort pulses which require high dispersion and large mode area to secure high stretching ratio and for ensuring distortionless pulses. In this line, we suggest a novel design of photonic quasi-crystal fiber (PQF) to achieve the desired high normal group velocity dispersion (GVD) of 1000 ps2/km at 1.06 μm and inner core effective mode area as 35 μm2 . These unique properties have been exploited to achieve a high stretching ratio (>; 105 ) as well as less nonlinearity, which, in turn, results in a distortionless fiber stretcher for an Yb-doped high-energy ultrafast fiber laser system based on chirped pulse amplification.
TL;DR: The first carrier-envelope phase (CEP)-stabilized chirped pulse amplification system with pulse peak-powers in the terawatt regime is demonstrated and single shot measurements of the residual CEP jitter at the full repetition rate show an excellent root-mean-square value.
Abstract: We demonstrate the first carrier-envelope phase (CEP)-stabilized chirped pulse amplification system with pulse peak-powers in the terawatt regime. The system, which eventually is intended to be used in the generation of isolated attosecond pulses, consists of two consecutive multipass amplification stages. The first amplification stage is a commercial CEP-stable kHz system including a single 13-pass amplifier reaching a pulse energy of 2.3 mJ. Pulses are picked after the first stage at a repetition rate of 50 Hz and are further amplified in a 5-pass power-amplifier to pulse energies that reach up to 80 mJ before compression. After compression the pulse energy is 35mJ at a pulse duration of 32 fs, signifying a peak power of 1.1 terawatt. Peak-powers exceeding 1.5 TW should easily be achievable by improving the efficiency of the grating compressor. The CEP-stability of the terawatt system is demonstrated by single shot measurements of the residual CEP jitter at the full repetition rate and show an excellent root-mean-square value of 315 mrad.
TL;DR: Time response of the Electro-Optic effect makes possible shaping at a high repetition rate or stabilization of the CEP of ultra short CPA laser systems.
Abstract: We present a new method to control the Carrier-Envelope Phase of ultra-short laser pulses by using the linear Electro-Optic Effect. Experimental demonstration is carried out on a Chirped Pulse Amplification based laser. Phase shifts greater than π radian can be obtained by applying moderate voltage on a LiNbO3 crystal with practically no changes to all other parameters of the pulse with the exception of its group delay. Time response of the Electro-Optic effect makes possible shaping at a high repetition rate or stabilization of the CEP of ultra short CPA laser systems.
Patent•
13 Sep 2011
TL;DR: Techniques and devices for producing short laser pulses based on chirped pulse amplification are described in this paper, with a focus on the use of chirping pulses for short laser bursts.
Abstract: Techniques and devices for producing short laser pulses based on chirped pulse amplification.
TL;DR: Numerical simulations, agreeing well with experimental data, yield a peak power of 5.7 GW at a pulse energy of 380 µJ making this an interesting source for high harmonic generation at high repetition rate and average power.
Abstract: We present simple and compact (1.5m x 0.5m footprint) post-compression of a state-of-the-art fiber chirped pulse amplification system. By using two stage nonlinear compression in noble gas filled hollow core fibers we shorten 1 mJ, 480 fs, 50 kHz pulses. The first stage is a 53 cm long, 200 µm inner diameter fiber filled with xenon with subsequent compression in a chirped mirror compressor. A 20 cm, 200 µm inner diameter fiber filled with argon further broadens the spectrum in a second stage and compression is achieved with another set of chirped mirrors. The average power is 24.5 W/19 W after the first/second stage, respectively. Compression to 35 fs is achieved. Numerical simulations, agreeing well with experimental data, yield a peak power of 5.7 GW at a pulse energy of 380 µJ making this an interesting source for high harmonic generation at high repetition rate and average power.
TL;DR: This paper presents an active time domain technique to generate parabolic pulses for chirped pulse amplification applications, and results of pulse shaping with a pulse train from a mode-locked laser are presented, with a residual error of less than 5%.
Abstract: Self-phase modulation in fiber amplifiers can significantly degrade the quality of compressed pulses in chirped pulse amplification systems. Parabolic pulses with linear frequency chirp are suitable for suppressing nonlinearities, and to achieve high peak power pulses after compression. In this paper, we present an active time domain technique to generate parabolic pulses for chirped pulse amplification applications. Pulses from a mode-locked laser are temporally stretched and launched into an amplitude modulator, where the drive voltage is designed using the spectral shape of the input pulse and the transfer function of the modulator, resulting in the generation of parabolic pulses. Experimental results of pulse shaping with a pulse train from a mode-locked laser are presented, with a residual error of less than 5%. Moreover, an extinction ratio of 27 dB is achieved, which is ideal for chirped pulse amplification applications.
TL;DR: In this article, a few-cycle laser pulses generated by optical parametric chirped pulse amplification were used to achieve sub-cycle light-wave control of electrons at a carrier wavelength of 2.1
Abstract: Using few-cycle laser pulses generated by optical parametric chirped pulse amplification, sub-cycle light-wave control of electrons was achieved at a carrier wavelength of 2.1 μm. We demonstrate the sub-cycle light-wave control in the case of strong field ionization of xenon atoms. Angle-resolved spectra of electrons emitted in the photoionization process were recorded as a function of the carrier-envelope phase (CEP) using an electron imaging technique. We observed a clear CEP-dependent asymmetry in the electron momentum distribution.
Patent•
01 Feb 2011
TL;DR: In this article, a chirped pulse amplification (CPA) system comprises an optical pulse stretcher and a optical pulse compressor that are mismatched in that the pulse compressor includes a bulk optical grating while the pulse stretchers does not.
Abstract: A chirped pulse amplification (CPA) system comprises an optical pulse stretcher and an optical pulse compressor that are mismatched in that the optical pulse compressor includes a bulk optical grating while the optical pulse stretcher does not. High order dispersion compensation is provided by an optical phase mask disposed within the optical pulse compressor.
TL;DR: In this article, the performance of chirped pulse amplification at single pass free-electron laser (FEL) amplifier is studied through numerical simulations using 1D time-dependent code GOFEL-P.
TL;DR: In this article, an all-fiber structured supercontinuum source based on chirped pulse amplification (CPA) technology and the use of nonlinear photonic crystal fiber was constructed.
Abstract: An all-fiber structured supercontinuum source based on chirped pulse amplification (CPA) technology and the use of nonlinear photonic crystal fiber was constructed. By experimentally varying fiber stretcher length in CPA laser source, we can change the spectral coverage and therefore the percentage of visible light in the produced supercontinuum at output of nonlinear photonic crystal fiber, while the average supercontinuum power always keeps at watts of level. The all-fiber structured feature and the capability of changing supercontinuum spectral coverage make this CPA system a promising implement for different applications that require different broad band spectrum.
Patent•
09 Aug 2011
TL;DR: In this paper, the authors present a system and method for improving dispersion management when using hollow core photonic bandgap fibers for pulse compression, where the fiber assembly outputs a pulse compression at less than 200 fs.
Abstract: Embodiments of the present invention are generally related to a fiber assembly, for example, in a chirped pulse amplification system, for all-fiber delivery of high energy femtosecond pulses. More specifically, embodiments of the present invention relate to a system and method for improving dispersion management when using hollow core photonic bandgap fibers for pulse compression. In one embodiment of the present invention, a fiber assembly comprises: an optical laser oscillator; a first fiber section for stretching the pulses from the laser oscillator, the first fiber section comprising a high order mode fiber; and a second fiber section for compressing the stretched pulses, connected to the first fiber section via a splice, the second fiber section comprising a hollow core photonic bandgap fiber; wherein the fiber assembly outputs a pulse compression at less than 200 fs.
TL;DR: In this article, an ultrashort and ultraintense pulses combination method is proposed, based on the spectral combination of parallel laser pulses, with complementary spectra, in chirped pulse amplification (CPA) laser systems.
Abstract: An ultrashort and ultraintense pulses combination method is proposed, based on the spectral combination of parallel laser pulses, with complementary spectra, in chirped pulse amplification (CPA) laser systems. In a proof-of-principle experiment, it is demonstrated that two long pulses of 330 fs can be overlapped in a collinear way, to produce a shorter pulse, of 190 fs. As a consequence, it is shown that the power for the combined pulse obtained is up to a factor of 1.7 larger than the sum of the peak powers of each individual pulse. The spectral phase of the combined pulse was characterized with λ/10 accuracy, using spectral interferometry. A way to implement the method at parallel CPA laser facilities, using no transmission optics, is indicated.
TL;DR: The use of a low finesse enhancement cavity resonant with a low average power and a high repetition rate pump source is shown to achieve 55% conversion efficiency into signal and idler from the coupled pump in an optical parametric process, whereas an equivalent amount of pump power in a single-pass configuration leads to negligible conversion.
Abstract: The use of a low finesse enhancement cavity resonant with a low average power (<1 W) and a high repetition rate (78 MHz) pump source is shown to achieve 55% conversion efficiency into signal and idler from the coupled pump in an optical parametric process, whereas an equivalent amount of pump power in a single-pass configuration leads to negligible conversion. Careful comparison of the intracavity conversion process to the single-pass case is performed to assess the underlying impedance matching that yields the high conversion results.
01 Jan 2011
TL;DR: A new method to broaden the amplification range in optical parametric amplification toward the bandwidth needed for single cycle femtosecond pulses by using two-color pumping of independent stages to sequentially amplify the long and short wavelength parts of the ultrabroadband seed pulses.
Abstract: We amplify ultrabroadband spectra to mJ energies: 575-1050nm by two-color-pumping and 675-1000nm by two-beam-pumping. We demonstrate the compressibility of these spectra and reveal the significance of a parametric phase imprinted on the signal.