能量和动量淀积深度分布的输运理论研究(英文)

Transport Theory Study of Depth Distribution Functions of Deposited Energy and Momentum

作者对于离子束轰击无限大非晶或多晶靶 ,基于材料的平移不变性 (TIM ) ,证明了能量和动量淀积深度分布函数的勒让德多项式展开系数必定为无限可微函数 ,并假定这些分布函数存在 作者揭示了TIM与线性输运理论 (LTE)之间的本质区别 :当总散射截面为无限大时 ,TIM仍然正确 ,但LTE就不再正确了 对于m =0 .5的幂散射截面 ,运用Pad啨逼近 ,由作者所构造的能量和动量淀积深度分布函数以及它们的勒让德多项式展开系数的深度分布函数 ,并没有发现所谓“奇点”和“不连续” 在某些情况下 。

Based on the translational invariance of a medium (TIM),the authors have proved that the coefficient functions of Legendre polynomials expansion of the depth distributions of the deposited energy and momentum must be infinitely differentiable functions in amorphous or polycrystalline infinite target by ion bombardment, and if these functions exist. The intrinsic difference between TIM and the linear transport equations (LTE) has been revealed: TIM remains correct but LTE is untenable if the total scattering cross section goes to infinite. The depth distributions of the deposited momentum and their coefficient functions of Legendre polynomials expansions have been reconstructed based on the Padé approximants for the power cross section with m=0.5 and no any 'singularity' or 'discontinuity' could be found. The component parallel to the incoming ion of the momentum deposited at the target surface may not change sign in some cases.