We developed a monochromatic crystal backlight imaging system for the double-cone ignition(DCI) scheme, employing a spherically bent quartz crystal. This system was used to measure the spatial distribution and tempora...We developed a monochromatic crystal backlight imaging system for the double-cone ignition(DCI) scheme, employing a spherically bent quartz crystal. This system was used to measure the spatial distribution and temporal evolution of the head-on colliding plasma from the two compressing cones in the DCI experiments. The influence of laser parameters on the x-ray backlighter intensity and spatial resolution of the imaging system was investigated. The imaging system had a spatial resolution of 10 μm when employing a CCD detector. Experiments demonstrated that the system can obtain time-resolved radiographic images with high quality, enabling the precise measurement of the shape, size, and density distribution of the plasma.展开更多
The spherical crystal imaging system,noted for its high energy spectral resolution(monochromaticity)and spatial resolution,is extensively applied in high energy density physics and inertial confinement fusion research...The spherical crystal imaging system,noted for its high energy spectral resolution(monochromaticity)and spatial resolution,is extensively applied in high energy density physics and inertial confinement fusion research.This system supports studies on fast electron transport,hydrodynamic instabilities,and implosion dynamics.The x-ray source,produced through laser-plasma interaction,emits a limited number of photons within short time scales,resulting in predominantly photon-starved images.Through ray-tracing simulations,we investigated the impact of varying crystal dimensions on the performance of a spherical crystal self-emission imager.We observed that increasing the crystal dimension leads to higher imaging efficiency but at the expense of monochromaticity,causing broader spectral acceptance and reduced spatial resolution.Furthermore,we presented a theoretical model to estimate the spatial resolution of the imaging system within a specific energy spectrum range,detailing the expressions for the effective size of the crystal.The spatial resolution derived from the model closely matches the numerical simulations.展开更多
Terahertz （THz） radiation has attracted much attention due to its wide potential applications. Though radiation can be generated with various ways, it is still a big challenge to obtain strong tabletop sources. Plas...Terahertz （THz） radiation has attracted much attention due to its wide potential applications. Though radiation can be generated with various ways, it is still a big challenge to obtain strong tabletop sources. Plasma, with the advantage of no damage limit, is a promising medium to generate strong THz radiation. This review reports recent advances on strong THz radiation generation from low-density gases and high-density solid targets at different laser intensities.展开更多
High coupling efficiency generation in water confined laser plasma propulsion is investigated. It is found that the coupling efficiency is enhanced over thirty times in water confined ablation compared to that of dire...High coupling efficiency generation in water confined laser plasma propulsion is investigated. It is found that the coupling efficiency is enhanced over thirty times in water confined ablation compared to that of direct ablation. From calculation of the ablation pressure induced by the plasma on the target surface, it is realized that high coupling efficiency is attributed to the confinement of the water layer on the plasma expansion.展开更多
Harmonics generated by an intense femtosecond Gaussian laser pulse normally incident on a spiral-shaped thin foil target were studied. By using two-dimensional （2D） particle-in-cell （PIC） simulation, we observed e...Harmonics generated by an intense femtosecond Gaussian laser pulse normally incident on a spiral-shaped thin foil target were studied. By using two-dimensional （2D） particle-in-cell （PIC） simulation, we observed evident odd harmonics signals in the reflection direction and found that the reflected field has a helical structure determined by the target shape. This method provides a new way to generate an intense ultraviolet vortex with high-order topological charge by use of ultrahigh intense laser-driven harmonics.展开更多
基金Project supported by the staff of the Shenguang-Ⅱ upgrade Laser facilityThis study was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25010100,XDA25010300,XDA25030100,XDA25030200,and XDA25051000)+2 种基金the National Natural Science Foundation of China(Grant Nos.11827807 and 12105359)the Open Foundation of Key Laboratory of High Power Laser and Physics of Chinese Academy of Sciences(Grant No.SGKF202105)the Chinese Academy of Sciences Youth Interdisciplinary Team(Grant No.JCTD-2022-05).
文摘We developed a monochromatic crystal backlight imaging system for the double-cone ignition(DCI) scheme, employing a spherically bent quartz crystal. This system was used to measure the spatial distribution and temporal evolution of the head-on colliding plasma from the two compressing cones in the DCI experiments. The influence of laser parameters on the x-ray backlighter intensity and spatial resolution of the imaging system was investigated. The imaging system had a spatial resolution of 10 μm when employing a CCD detector. Experiments demonstrated that the system can obtain time-resolved radiographic images with high quality, enabling the precise measurement of the shape, size, and density distribution of the plasma.
基金Project supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25051000,XDA25010100,XDA25010300,XDA25030100,and XDA25030200)。
文摘The spherical crystal imaging system,noted for its high energy spectral resolution(monochromaticity)and spatial resolution,is extensively applied in high energy density physics and inertial confinement fusion research.This system supports studies on fast electron transport,hydrodynamic instabilities,and implosion dynamics.The x-ray source,produced through laser-plasma interaction,emits a limited number of photons within short time scales,resulting in predominantly photon-starved images.Through ray-tracing simulations,we investigated the impact of varying crystal dimensions on the performance of a spherical crystal self-emission imager.We observed that increasing the crystal dimension leads to higher imaging efficiency but at the expense of monochromaticity,causing broader spectral acceptance and reduced spatial resolution.Furthermore,we presented a theoretical model to estimate the spatial resolution of the imaging system within a specific energy spectrum range,detailing the expressions for the effective size of the crystal.The spatial resolution derived from the model closely matches the numerical simulations.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10925421,11135012,11105217, and 11121504)
文摘Terahertz （THz） radiation has attracted much attention due to its wide potential applications. Though radiation can be generated with various ways, it is still a big challenge to obtain strong tabletop sources. Plasma, with the advantage of no damage limit, is a promising medium to generate strong THz radiation. This review reports recent advances on strong THz radiation generation from low-density gases and high-density solid targets at different laser intensities.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60321003, 10510490 and 10334110, and the National Hi-tech ICF Programme of China.
文摘High coupling efficiency generation in water confined laser plasma propulsion is investigated. It is found that the coupling efficiency is enhanced over thirty times in water confined ablation compared to that of direct ablation. From calculation of the ablation pressure induced by the plasma on the target surface, it is realized that high coupling efficiency is attributed to the confinement of the water layer on the plasma expansion.
基金Project supported by the National Basic Research Program of China(Grant Nos.2013CBA01501 and 2013CBA01504)the National Key Scientific Instrument and Equipment Development Project,China(Grant No.2012YQ120047)+1 种基金CAS Key Program and National Natural Science Foundation of China(Grant Nos.11135012 and 11375262)a Project of Higher Educational Science and Technology Program of Shandong Province,China(Grant No.J11LA52)
文摘Harmonics generated by an intense femtosecond Gaussian laser pulse normally incident on a spiral-shaped thin foil target were studied. By using two-dimensional （2D） particle-in-cell （PIC） simulation, we observed evident odd harmonics signals in the reflection direction and found that the reflected field has a helical structure determined by the target shape. This method provides a new way to generate an intense ultraviolet vortex with high-order topological charge by use of ultrahigh intense laser-driven harmonics.
