Understanding the behaviour of matter under conditions of extreme temperature,pressure,density and electromagnetic fields has profound effects on our understanding of cosmologic objects and the formation of the univer...Understanding the behaviour of matter under conditions of extreme temperature,pressure,density and electromagnetic fields has profound effects on our understanding of cosmologic objects and the formation of the universe.Lacking direct access to such objects,our interpretation of observed data mainly relies on theoretical models.However,such models,which need to encompass nuclear physics,atomic physics and plasma physics over a huge dynamic range in the dimensions of energy and time,can only provide reliable information if we can benchmark them to experiments under well-defined laboratory conditions.Due to the plethora of effects occurring in this kind of highly excited matter,characterizing isolated dynamics or obtaining direct insight remains challenging.High-density plasmas are turbulent and opaque for radiation below the plasma frequency and allow only near-surface insight into ionization processes with visible wavelengths.Here,the output of a high-harmonic seeded laser-plasma amplifier using eightfold ionized krypton as the gain medium operating at a 32.8 nm wavelength is ptychographically imaged.A complexvalued wavefront is observed in the extreme ultraviolet(XUV)beam with high resolution.Ab initio spatio-temporal Maxwell–Bloch simulations show excellent agreement with the experimental observations,revealing overionization of krypton in the plasma channel due to nonlinear laser-plasma interactions,successfully validating this four-dimensional multiscale model.This constitutes the first experimental observation of the laser ion abundance reshaping a laserplasma amplifier.The presented approach shows the possibility of directly modelling light-plasma interactions in extreme conditions,such as those present during the early times of the universe,with direct experimental verification.展开更多
基金funding from the European Community’s Horizon 2020 research and innovation program under grant agreement n°654148(LASERLAB EUROPE)support from the Max Planck Society(Max Planck Research Group)and the Federal Ministry of Education and Research(BMBF)under“Make our Planet Great Again-German Research Initiative”(Grant No.57427209“QUESTforENERGY”)implemented by DAAD+4 种基金support from the Federal State of Thuringia and the European Social Fund(ESF)Project 2018 FGR 0080BMBF-project 05P19SJFA1 within Verbundprojekt 05P2018(ErUM-FSP T05)support from the European Community’s Horizon 2020 research and innovation program under grant agreement 665207,project VOXELthe Universidad Politecnica de Madrid(UPM),project DERKETA,the Comunidad de Madrid and UPM,linea de actuacion estimulo a la investigacion de jovenes doctores,project CROM and the Spanish Ministerio de Ciencia e Innovacion through a Ramon y Cajal RYC2018-026238-I fellowshipsupported by“Investissements d’Avenir”Labex PALM(ANR-10-LABX-0039-PALM).
文摘Understanding the behaviour of matter under conditions of extreme temperature,pressure,density and electromagnetic fields has profound effects on our understanding of cosmologic objects and the formation of the universe.Lacking direct access to such objects,our interpretation of observed data mainly relies on theoretical models.However,such models,which need to encompass nuclear physics,atomic physics and plasma physics over a huge dynamic range in the dimensions of energy and time,can only provide reliable information if we can benchmark them to experiments under well-defined laboratory conditions.Due to the plethora of effects occurring in this kind of highly excited matter,characterizing isolated dynamics or obtaining direct insight remains challenging.High-density plasmas are turbulent and opaque for radiation below the plasma frequency and allow only near-surface insight into ionization processes with visible wavelengths.Here,the output of a high-harmonic seeded laser-plasma amplifier using eightfold ionized krypton as the gain medium operating at a 32.8 nm wavelength is ptychographically imaged.A complexvalued wavefront is observed in the extreme ultraviolet(XUV)beam with high resolution.Ab initio spatio-temporal Maxwell–Bloch simulations show excellent agreement with the experimental observations,revealing overionization of krypton in the plasma channel due to nonlinear laser-plasma interactions,successfully validating this four-dimensional multiscale model.This constitutes the first experimental observation of the laser ion abundance reshaping a laserplasma amplifier.The presented approach shows the possibility of directly modelling light-plasma interactions in extreme conditions,such as those present during the early times of the universe,with direct experimental verification.