高熵合金在相穩定與機械性質的優異，讓越來越多的學者與機構爭相投入研究，但其光學性質與導電性質的優劣卻鮮有人探討，固本研究的目標之一便是設計出一套模擬方法，可用來粗估高熵合金的功函數、反射率與導電度等性質。
一開始為了開發能取代現有的量測探針如錸鎢探針、鈹銅探針等，本研究選定了機械性質佳的高熵合金作為對象，其中又以NbMoTaW是由幾個導電度高的元素所組成，故最後計算的對象為等比例的Nb0.25Mo0.25Ta0.25W0.25與調比例的Nb0.15Mo0.35Ta0.15W0.35和Nb0.15Mo0.15Ta0.35W0.35等三種材料，因等比例的結構在先前實驗室學長的努力下已累積不少的計算成果，所以本研究會著重於調比例的計算和三者性質的比較，並探討雞尾酒效應是否可同樣應用於上述的性質當中。

In this study, the work function, reflectance, and frequency dependent conductivity are successful to be simulated. On one hand using linear combination of work function and conductivity of elements can provide a good prediction of them of HEAs, but on the other hand this method cannot be applied on reflectance simulation. Moreover, the AC conductivity of HEAs from low frequency to high frequency has been investigated by ab-initio calculations and the Drude-Lorentz (DL) model. The DL model could give good predictions of the AC conductivity of HEAs from several Hz to 10^16 Hz. At a frequency above 10^14 Hz where the Lorentz model dominates the AC conductivity could be simply estimated by the linear combination of the conductivity of pure elements according to the stoichiometry. At a frequency below 10^14 Hz, an empirical relaxation time obtained from experiments is needed to improve the predictions. This is due to the properties of free electrons change with the materials' composition.

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