Here,we report the recent progress on the front end developed for the 100 PW-class laser facility.Using 3 stages of optical parametric chirped-pulse amplification(OPCPA)based on lithium triborate(LBO)crystals,we reali...Here,we report the recent progress on the front end developed for the 100 PW-class laser facility.Using 3 stages of optical parametric chirped-pulse amplification(OPCPA)based on lithium triborate(LBO)crystals,we realized a 5.26 J/0.1 Hz amplified output with a bandwidth over 200 nm near the center wavelength of 925 nm.After the compressor,we obtained a pulse duration of 13.4 fs.As the compression efficiency reached 67%,this OPCPA front end could potentially support a peak power of 263 TW at a repetition rate of 0.1 Hz.To the best of our knowledge,among all the 100 TW-level OPCPA systems,it shows the widest spectral width,the shortest pulse duration,and it is also the first OPCPA system working at a repetition-rate mode.展开更多
We presented a broadband optical parametric chirped pulse amplification(OPCPA)system based on dual-crystal spectra cascading amplification in the short-wave infrared(SWIR)region.By cascading two crystals with differen...We presented a broadband optical parametric chirped pulse amplification(OPCPA)system based on dual-crystal spectra cascading amplification in the short-wave infrared(SWIR)region.By cascading two crystals with different phase-matching angles,the impact of gain bandwidth narrowing in OPCPA is reduced.In addition,due to the different phase-matching wavelengths,the energy backflow of the idler pulses is also mitigated,thereby enhancing the overall energy conversion efficiency of the system.Ultimately,SWIR pulses with a full-width at half-maximum(FWHM)exceeding 110 nm,a near Fourier-transform limit(FTL)pulse duration of 42.15 fs,and a pulse energy of 30 mJ are obtained(25.9%pump energy conversion efficiency),corresponding to a peak power of 0.75 TW.Compared to single-crystal amplification,this configuration achieves an 80 nm expansion in FWHM,the output pulse duration is reduced by more than 40%,the pump efficiency is increased by 17.22%,and a 2.3-time enhancement in peak power is achieved.This high-energy,terawatt-class SWIR source has significant applications in strong-field physics,including high-intensity THz and water-window X-ray generation,among other areas.展开更多
High-power femtosecond lasers beyond 5μm are attractive for strong-field physics with mid-infrared(IR)fields but are difficult to scale up.In optical parametric chirped-pulse amplification(OPCPA)at mid-IR wavelengths...High-power femtosecond lasers beyond 5μm are attractive for strong-field physics with mid-infrared(IR)fields but are difficult to scale up.In optical parametric chirped-pulse amplification(OPCPA)at mid-IR wavelengths,a nonlinear crystal is vital,and its transmittance,dispersion,nonlinear coefficient and size determine the achievable power and wavelength.OPCPA beyond 5μm routinely relies on semiconductor crystals because common oxide crystals are not transparent in this spectral range.However,the small size and low damage threshold of semiconductor crystals fundamentally limit the peak power to gigawatts.In this paper,we design a terawatt-class OPCPA system at 5.2μm based on a new kind of oxide crystal of La3Ga5.5Nb0.5O14(LGN).The extended transparent range,high damage threshold,superior phase-matching characteristics and large size of LGN enable the generation of 0.13 TW seven-cycle pulses at5.2μm.This design fully relies on the state-of-the-art OPCPA technology of an octave-spanning ultrafast Ti:sapphire laser and a thin-disk Yb:YAG laser,offering the performance characteristics of high power,a high repetition rate and a stable carrier-envelope phase.展开更多
基金Shanghai Municipal Science and Technology Major Project(2017SHZDZX02)Natural Science Foundation of Shanghai(20ZR1464600)+5 种基金This work is funded by the National Key R&D Program of China(2017YFE0123700)Program of Shanghai Academic/Technology Research Leader(18XD1404200)and International Partnership Program of Chinese Academy of Sciences(181231KYSB20200040)Shanghai Sailing Program(19YF1453100)National Natural Science Foundation of China(61925507)Youth Innovation Promotion Association of the Chinese Academy of Sciences The Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1603)。
文摘Here,we report the recent progress on the front end developed for the 100 PW-class laser facility.Using 3 stages of optical parametric chirped-pulse amplification(OPCPA)based on lithium triborate(LBO)crystals,we realized a 5.26 J/0.1 Hz amplified output with a bandwidth over 200 nm near the center wavelength of 925 nm.After the compressor,we obtained a pulse duration of 13.4 fs.As the compression efficiency reached 67%,this OPCPA front end could potentially support a peak power of 263 TW at a repetition rate of 0.1 Hz.To the best of our knowledge,among all the 100 TW-level OPCPA systems,it shows the widest spectral width,the shortest pulse duration,and it is also the first OPCPA system working at a repetition-rate mode.
基金National Key Research and Development Program of China(2023YFA1608504,2022YFA1604401)National Natural Science Foundation of China(12388102,22227901,62305353,U22A2090)+2 种基金Shanghai Science and Technology Committee Program(22DZ1100300,22560780100,23560750200)Talent Plan of Shanghai Branch,Chinese Academy of SciencesCAS Project for Young Scientists in Basic Research(YSBR-115).
文摘We presented a broadband optical parametric chirped pulse amplification(OPCPA)system based on dual-crystal spectra cascading amplification in the short-wave infrared(SWIR)region.By cascading two crystals with different phase-matching angles,the impact of gain bandwidth narrowing in OPCPA is reduced.In addition,due to the different phase-matching wavelengths,the energy backflow of the idler pulses is also mitigated,thereby enhancing the overall energy conversion efficiency of the system.Ultimately,SWIR pulses with a full-width at half-maximum(FWHM)exceeding 110 nm,a near Fourier-transform limit(FTL)pulse duration of 42.15 fs,and a pulse energy of 30 mJ are obtained(25.9%pump energy conversion efficiency),corresponding to a peak power of 0.75 TW.Compared to single-crystal amplification,this configuration achieves an 80 nm expansion in FWHM,the output pulse duration is reduced by more than 40%,the pump efficiency is increased by 17.22%,and a 2.3-time enhancement in peak power is achieved.This high-energy,terawatt-class SWIR source has significant applications in strong-field physics,including high-intensity THz and water-window X-ray generation,among other areas.
基金supported in part by the National Natural Science Foundation of China(Nos.6170512861727820 and 91850203)Science and Technology Commission of Shanghai Municipality(Nos.17YF1409100 and17ZR1414000)。
文摘High-power femtosecond lasers beyond 5μm are attractive for strong-field physics with mid-infrared(IR)fields but are difficult to scale up.In optical parametric chirped-pulse amplification(OPCPA)at mid-IR wavelengths,a nonlinear crystal is vital,and its transmittance,dispersion,nonlinear coefficient and size determine the achievable power and wavelength.OPCPA beyond 5μm routinely relies on semiconductor crystals because common oxide crystals are not transparent in this spectral range.However,the small size and low damage threshold of semiconductor crystals fundamentally limit the peak power to gigawatts.In this paper,we design a terawatt-class OPCPA system at 5.2μm based on a new kind of oxide crystal of La3Ga5.5Nb0.5O14(LGN).The extended transparent range,high damage threshold,superior phase-matching characteristics and large size of LGN enable the generation of 0.13 TW seven-cycle pulses at5.2μm.This design fully relies on the state-of-the-art OPCPA technology of an octave-spanning ultrafast Ti:sapphire laser and a thin-disk Yb:YAG laser,offering the performance characteristics of high power,a high repetition rate and a stable carrier-envelope phase.
