The Experts below are selected from a list of 29997 Experts worldwide ranked by ideXlab platform
Andreas Tunnermann - One of the best experts on this subject based on the ideXlab platform.
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self Compression in a solid fiber to 24 mw peak power with few cycle pulses at 2 μm wavelength
Optics Letters, 2015Co-Authors: Christian Gaida, Jens Limpert, Martin Gebhardt, Fabian Stutzki, Cesar Jauregui, Andreas TunnermannAbstract:We report on the experimental realization of a compact, fiber-based, ultrashort-pulse laser system in the 2 μm wavelength region delivering 24 fs pulse duration with 24 MW pulse peak power and 24.6 W average power. This performance level has been enabled by the favorable quadratic wavelength-dependence of the self-focusing limit, which has been experimentally verified to be at approximately 24 MW for circular polarization in a solid-core fused-silica fiber operated at a wavelength around 2 μm. The anomalous dispersion in this wavelength region allows for a simultaneous nonlinear spectral broadening and temporal pulse Compression. This makes an additional Compression Stage redundant and facilitates a very simple and power-scalable approach. Simulations that include both the nonlinear pulse evolution and the transverse optical Kerr effect support the experimental results.
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sub 25 fs pulses from solid core nonlinear Compression Stage at 250 w of average power
Optics Letters, 2012Co-Authors: Christoph Jocher, Tino Eidam, Steffen Hadrich, Jens Limpert, Andreas TunnermannAbstract:We report on a highpower femtosecond fiber chirped-pulse amplification system with an excellent beam quality (M2=1.2) operating at 250 MHz repetition rate. We demonstrate nonlinear Compression in a solid-core photonic crystal fiber at unprecedented average power levels. By exploiting self-phase modulation with subsequent chirped-mirror Compression we achieve pulse shortening by more than one order of magnitude to 23 fs pulses. The use of circular polarization allows higher than usual peak powers in the broadening fiber resulting in compressed 0.9 μJ pulse energy and a peak power of 34 MW at 250 W of average power (M2=1.3). This system is well suited for driving cavity-enhanced high-repetition rate high-harmonic generation.
L. Lavenu - One of the best experts on this subject based on the ideXlab platform.
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High-power two-cycle ultrafast source based on hybrid nonlinear Compression
Optics Express, 2019Co-Authors: L. Lavenu, M. Natile, Y. Zaouter, Marc Hanna, F. Guichard, Xavier Délen, Patrick GeorgesAbstract:We demonstrate a hybrid dual-Stage nonlinear Compression scheme, which allows the temporal Compression of 330 fs-pulses down to 6.8 fs-pulses, with an overall transmission of 61%. This high transmission is obtained by using a first Compression Stage based on a gas-filled multipass cell, and a second Stage based on a large-core gas-filled capillary. The source output is fully characterized in terms of spectral, temporal, spatial, and short-and long-term stability properties. The system's compactness, stability, and high average power makes it ideally suited to drive high photon flux XUV sources through high harmonic generation.
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High-energy few-cycle Yb-doped fiber amplifier source based on a single nonlinear Compression Stage
Optics Express, 2017Co-Authors: L. Lavenu, M. Natile, Florent Guichard, Y. Zaouter, Marc Hanna, E. Mottay, P. GeorgesAbstract:A simple, compact, and efficient few-cycle laser source at a central wavelength of 1 µm is presented. The system is based on a high-energy femtosecond ytterbium-doped fiber amplifier delivering 130 fs, 250 µJ pulses at 200 kHz, corresponding to 1.5 GW of peak power and an average power of 50 W. The unprecedented short pulse duration at the output of this system is obtained by use of spectral intensity and phase shaping, allowing for both gain narrowing mitigation and the compensation of the nonlinear accumulated spectral phase. This laser source is followed by a single-Stage of nonlinear Compression in a xenon-filled capillary, allowing for the generation of 14 fs, 120 µJ pulses at 200 kHz resulting in 24 W of average power. High-harmonic generation driven by this type of source will trigger numerous new applications in the XUV range and attosecond science.
Audrius Bagdanavicius - One of the best experts on this subject based on the ideXlab platform.
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exergy and exergoeconomic analysis of a compressed air energy storage combined with a district energy system
Energy Conversion and Management, 2014Co-Authors: Audrius BagdanaviciusAbstract:Abstract The potential for using heat generated during the Compression Stage of a Compressed Air Energy Storage system was investigated using exergy and exergoeconomic analysis. Two Compressed Air Energy Storage systems were analysed: Compressed Air Energy Storage (CAES) and Compressed Air Energy Storage combined with Thermal Storage (CAES-TS) connected to a district heating network. The maximum output of the CAES was 100 MWe and the output of the CAES-TS was 100 MWe and 105 MWth. The study shows that 308 GW h/year of electricity and 466 GW h/year of fuel are used to generate 375 GW h/year of electricity. During the Compression of air 289 GW h/year of heat is generated, which is wasted in the CAES and used for district heating in the CAES-TS system. Energy efficiency of the CAES system was around 48% and the efficiency of CAES-TS was 86%. Exergoeconomic analysis shows that the exergy cost of electricity generated in the CAES was 13.89 ¢/kW h, and the exergy cost of electricity generated in the CAES-TS was 11.20 ¢/kW h. The exergy cost of heat was 22.24 ¢/kW h in the CAES-TS system. The study shows that CAES-TS has the potential to be used both as energy storage and heat source and could be a useful tool for balancing overall energy demand and supply.
Maurizio Barbato - One of the best experts on this subject based on the ideXlab platform.
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analysis of an integrated packed bed thermal energy storage system for heat recovery in compressed air energy storage technology
Applied Energy, 2017Co-Authors: Inigo Ortegafernandez, Simone Zavattoni, Javier Rodriguezaseguinolaza, Bruno Daguanno, Maurizio BarbatoAbstract:Abstract Compressed air energy storage (CAES) represents a very attracting option to grid electric energy storage. Although this technology is mature and well established, its overall electricity-to-electricity cycle efficiency is lower with respect to other alternatives such as pumped hydroelectric energy storage. A meager heat management strategy in the CAES technology is among the main reasons of this gap of efficiency. In current CAES plants, during the Compression Stage, a large amount of thermal energy is produced and wasted. On the other hand, during the electricity generation Stage, an extensive heat supply is required, currently provided by burning natural gas. In this work, the coupling of both CAES Stages through a thermal energy storage (TES) unit is introduced as an effective solution to achieve a noticeable increase of the overall CAES cycle efficiency. In this frame, the thermal energy produced in the Compression Stage is stored in a TES unit for its subsequent deployment during the expansion Stage, realizing an Adiabatic-CAES plant. The present study addresses the conceptual design of a TES system based on a packed bed of gravel to be integrated in an Adiabatic-CAES plant. With this objective, a complete thermo-fluid dynamics model has been developed, including the implications derived from the TES operating under variable-pressure conditions. The formulation and treatment of the high pressure conditions were found being particularly relevant issues. Finally, the model provided a detailed performance and efficiency analysis of the TES system under charge/discharge cyclic conditions including a realistic operative scenario. Overall, the results show the high potential of integrating this type of TES systems in a CAES plant.
P. Georges - One of the best experts on this subject based on the ideXlab platform.
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High-energy few-cycle Yb-doped fiber amplifier source based on a single nonlinear Compression Stage
Optics Express, 2017Co-Authors: L. Lavenu, M. Natile, Florent Guichard, Y. Zaouter, Marc Hanna, E. Mottay, P. GeorgesAbstract:A simple, compact, and efficient few-cycle laser source at a central wavelength of 1 µm is presented. The system is based on a high-energy femtosecond ytterbium-doped fiber amplifier delivering 130 fs, 250 µJ pulses at 200 kHz, corresponding to 1.5 GW of peak power and an average power of 50 W. The unprecedented short pulse duration at the output of this system is obtained by use of spectral intensity and phase shaping, allowing for both gain narrowing mitigation and the compensation of the nonlinear accumulated spectral phase. This laser source is followed by a single-Stage of nonlinear Compression in a xenon-filled capillary, allowing for the generation of 14 fs, 120 µJ pulses at 200 kHz resulting in 24 W of average power. High-harmonic generation driven by this type of source will trigger numerous new applications in the XUV range and attosecond science.