Characteristics and geometry optimization of a hollow cone for guiding and focusing laser light  

作　　者：ZENG XiaHui FAN DianYuan 

机构地区：[1]Department of Physics&Electronic Information Engineering,Minjiang University,Fuzhou 350108,China [2]Shanghat Instinute of Opttcs and Free Mechantcs,Chinese Academy of Sciences,Shanghai 201800,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2012年第2期204-212,共9页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.61359020101-3);the National High Technology Research;Development Program for Inertial Confinement Fusion of China

摘　　要：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.A highly focused beam with spot radius of around 1 m 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.

关 键 词：laser beam focusing hollow cone finite-difference time-domain （FDTD） method 

分 类 号：TN622[电子电信—电路与系统] TQ172.623[化学工程—水泥工业]