10 PW-class lasers irradiating overcritical plasmas in the quantum electrodynamics regime promise to generate ultrabrightγ-ray sources in the laboratory.Here using two-dimensional particle-in-cell simulations,we repo...10 PW-class lasers irradiating overcritical plasmas in the quantum electrodynamics regime promise to generate ultrabrightγ-ray sources in the laboratory.Here using two-dimensional particle-in-cell simulations,we report highly efficientγ-ray generation in the parameter regime of 10 PW-class lasers at an intensity level of 10^(23)W cm^(–2)interaction with heavy-ion plasmas which have large-scale preplasmas.The laser-to-γ-ray(>1 MeV)energy conversion efficiency reaches close to 60%with an above 10^(14)γ-photons/pulse.The averageγ-photon energy is about 14 MeV with the highest photon energy exceeding 1 GeV.The high-energyγ-photons are mainly directed in the forward direction.We also find that plane target geometry is efficient enough for high powerγ-ray radiation,which is beneficial for easing the difficulty of complex target manufacturing and alignment in experiments.展开更多
Mid-infrared(MIR)ultra-short pulses with multiple spectral-band coverage and good freedom in spectral and temporal shaping are desired by broad applications such as steering strong-field ionization,investigating bound...Mid-infrared(MIR)ultra-short pulses with multiple spectral-band coverage and good freedom in spectral and temporal shaping are desired by broad applications such as steering strong-field ionization,investigating bound-electron dynamics,and minimally invasive tissue ablation.However,the existing methods of light transient generation lack freedom in spectral tuning and require sophisticated apparatus for complicated phase and noise control.Here,with both numerical analysis and experimental demonstration,we report the first attempt,to the best our knowledge,at generating MIR pulses with dual-wavelength spectral shaping and exceptional freedom of tunability in both the lasing wavelength and relative spectral amplitudes,based on a relatively simple and compact apparatus compared to traditional pulse synthesizers.The proof-of-concept demonstration in steering the high-harmonic generation in a polycrystalline ZnSe plate is facilitated by dual-wavelength MIR pulses shaped in both spectral and temporal domains,spanning from 5.6 to 11.4μm,with multi-microjoule pulse energy and hundred-milliwatt average power.Multisets of harmonics corresponding to different fundamental wavelengths are simultaneously generated in the deep ultraviolet region,and both the relative strength of individual harmonics sets and the spectral shapes of harmonics are harnessed with remarkable freedom and flexibility.This work would open new possibilities in exploring femtosecond control of electron dynamics and light–matter interaction in composite molecular systems.展开更多
基金supported in part by the National Key Laboratory of Shock Wave and Detonation Physics(No.JCKYS2020212015)National Natural Science Foundation of China(No.12175157)the Fundamental Research Funds for the Central Universities(No.YJ202025)。
文摘10 PW-class lasers irradiating overcritical plasmas in the quantum electrodynamics regime promise to generate ultrabrightγ-ray sources in the laboratory.Here using two-dimensional particle-in-cell simulations,we report highly efficientγ-ray generation in the parameter regime of 10 PW-class lasers at an intensity level of 10^(23)W cm^(–2)interaction with heavy-ion plasmas which have large-scale preplasmas.The laser-to-γ-ray(>1 MeV)energy conversion efficiency reaches close to 60%with an above 10^(14)γ-photons/pulse.The averageγ-photon energy is about 14 MeV with the highest photon energy exceeding 1 GeV.The high-energyγ-photons are mainly directed in the forward direction.We also find that plane target geometry is efficient enough for high powerγ-ray radiation,which is beneficial for easing the difficulty of complex target manufacturing and alignment in experiments.
基金the National Natural Science Foundation of China(62075144 and U22A2090)Sichuan Outstanding Youth Science and Technology Talents(2022JDJQ0031)Engineering Featured team Fund of Sichuan University(2020SCUNG105)。
文摘Mid-infrared(MIR)ultra-short pulses with multiple spectral-band coverage and good freedom in spectral and temporal shaping are desired by broad applications such as steering strong-field ionization,investigating bound-electron dynamics,and minimally invasive tissue ablation.However,the existing methods of light transient generation lack freedom in spectral tuning and require sophisticated apparatus for complicated phase and noise control.Here,with both numerical analysis and experimental demonstration,we report the first attempt,to the best our knowledge,at generating MIR pulses with dual-wavelength spectral shaping and exceptional freedom of tunability in both the lasing wavelength and relative spectral amplitudes,based on a relatively simple and compact apparatus compared to traditional pulse synthesizers.The proof-of-concept demonstration in steering the high-harmonic generation in a polycrystalline ZnSe plate is facilitated by dual-wavelength MIR pulses shaped in both spectral and temporal domains,spanning from 5.6 to 11.4μm,with multi-microjoule pulse energy and hundred-milliwatt average power.Multisets of harmonics corresponding to different fundamental wavelengths are simultaneously generated in the deep ultraviolet region,and both the relative strength of individual harmonics sets and the spectral shapes of harmonics are harnessed with remarkable freedom and flexibility.This work would open new possibilities in exploring femtosecond control of electron dynamics and light–matter interaction in composite molecular systems.
