AmpliHcation of spontaneous emissions at 19.6,23.2 and 23.6 nm have been observed by a “ultiple-Target Series Coupling”design in Ge plasma,.The combined length for four targets is up to 56mm.The gain length product(...AmpliHcation of spontaneous emissions at 19.6,23.2 and 23.6 nm have been observed by a “ultiple-Target Series Coupling”design in Ge plasma,.The combined length for four targets is up to 56mm.The gain length product(GL)of small signal is up to 18 for both lines at 23.2 and 23.6 nmt and the effective GL is 16.4 and 15.7 for these two lines respectively.This two lines are obviously tending to saturation.The divergence of x-ray laser beam is about 4 mrad.展开更多
A CW seeded femtosecond optical parametric amplifier, a compromise between OPG/OPA and strongly seeded OPA configurations, has been demonstrated. An independent CW Nd︰YAG laser with sub-watt power decreases the pump ...A CW seeded femtosecond optical parametric amplifier, a compromise between OPG/OPA and strongly seeded OPA configurations, has been demonstrated. An independent CW Nd︰YAG laser with sub-watt power decreases the pump threshold of the OPA and improves the stability of the output pulses considerably. Output signal energies as high as 30 μJ with pulse durations less than 250 fs near 1 μm are reported from this two-stage device.展开更多
We present the performance of a high-power Nd:glass laser system,which produces a 1.1 J,250 fs,7.3 nm broadband laser pulse based on the combination of optical parametric amplification(OPA) and chirped pulse amplifica...We present the performance of a high-power Nd:glass laser system,which produces a 1.1 J,250 fs,7.3 nm broadband laser pulse based on the combination of optical parametric amplification(OPA) and chirped pulse amplification(CPA).The two-stage OPA provides broadband seed pulses for the three-stage Nd:glass amplifiers based on the technology of CPA.Compared to the conventional oscillator seed source,the most important advantage of such a seed source supplied by the two-stage OPA is that it possesses the capacities of broad bandwidth and high energy.展开更多
A highly focused beam with spot radius of around 1 ktm and enhanced light intensity is obtained by using an open hollow cone. Two-dimensional and three-dimensional finite-difference time-domain simulations are perform...A highly focused beam with spot radius of around 1 ktm and enhanced light intensity is obtained by using an open hollow cone. Two-dimensional and three-dimensional finite-difference time-domain simulations are performed for clarifying light propagation characteristics and the cone geometry dependence of the cone-focused laser light. Two important parameters characterizing the cone-focusing effect are introduced, which are opening angle and cone tip size. By changing these parameters, the laser intensification, field spatial distribution at the cone tip and the near-field transmission can be controlled. Understanding this is quite important in designing the optimum cone shape for fast ignition and determining the basis for using hollow cone targets as devices for generating high energy charged particles.展开更多
基金Supported by the Laser Domain of the Chinese National High Technology Plan。
文摘AmpliHcation of spontaneous emissions at 19.6,23.2 and 23.6 nm have been observed by a “ultiple-Target Series Coupling”design in Ge plasma,.The combined length for four targets is up to 56mm.The gain length product(GL)of small signal is up to 18 for both lines at 23.2 and 23.6 nmt and the effective GL is 16.4 and 15.7 for these two lines respectively.This two lines are obviously tending to saturation.The divergence of x-ray laser beam is about 4 mrad.
基金This work was supported by the National Natural Science Foundation of China(Grant No.10104006)the 863 Project.
文摘A CW seeded femtosecond optical parametric amplifier, a compromise between OPG/OPA and strongly seeded OPA configurations, has been demonstrated. An independent CW Nd︰YAG laser with sub-watt power decreases the pump threshold of the OPA and improves the stability of the output pulses considerably. Output signal energies as high as 30 μJ with pulse durations less than 250 fs near 1 μm are reported from this two-stage device.
基金supported by the National Natural Science Foundation of China (Grant No.60890202)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No.20110161110012)+1 种基金the Department of Science and Technology of Hunan Province (Grant No.2011FJ3121)the Fundamental Research Funds for the Central Universities,Hunan University and SRF for ROCS,SEM
文摘We present the performance of a high-power Nd:glass laser system,which produces a 1.1 J,250 fs,7.3 nm broadband laser pulse based on the combination of optical parametric amplification(OPA) and chirped pulse amplification(CPA).The two-stage OPA provides broadband seed pulses for the three-stage Nd:glass amplifiers based on the technology of CPA.Compared to the conventional oscillator seed source,the most important advantage of such a seed source supplied by the two-stage OPA is that it possesses the capacities of broad bandwidth and high energy.
基金supported by the National Basic Research Program of China(Grant No.61359020101-3)the National High Technology ResearchDevelopment Program for Inertial Confinement Fusion of China
文摘A highly focused beam with spot radius of around 1 ktm and enhanced light intensity is obtained by using an open hollow cone. Two-dimensional and three-dimensional finite-difference time-domain simulations are performed for clarifying light propagation characteristics and the cone geometry dependence of the cone-focused laser light. Two important parameters characterizing the cone-focusing effect are introduced, which are opening angle and cone tip size. By changing these parameters, the laser intensification, field spatial distribution at the cone tip and the near-field transmission can be controlled. Understanding this is quite important in designing the optimum cone shape for fast ignition and determining the basis for using hollow cone targets as devices for generating high energy charged particles.
