electron metal meaning in English

(比铝轻的)镁合金。

In this thesis , a new finite difference time domain ( fdtd ) method is developed to treat a two - dimensional photonic crystal consisting of nearly - free - electron metals . the method is used to calculate the band structures and investigate defect modes and guide modes in such a photonic crystal
本论文首先发展了一种基于等离子模型的有限差分计算方法，并应用于二维金属光子晶体，有效地计算了该类光子晶体的能带结构。