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 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.