過去的研究中我們發現鉛金合金時，在合金𝑀̅附近能量－2 eV 的地方有一個拋物線的能帶，但配合鉛金合金的理論計算中，並無出現這個能帶，所以我們認為這個能帶來源不屬於鉛金合金。
進行更進一步的實驗及參考文獻後，我們發現此拋物線的能帶屬於Pb(111)的表面態，是由金的5d軌域6p和鉛的軌域耦合而成。於是我們萌生了新的想法：在低溫的時候，鍍金在Pb(111)上，不形成合金的情況下分析𝑀̅附近的表面態。
本篇論文中我們提出了金原子堆疊在Pb(111)上方的結構中，如何引導出不同於以往新的表面態，並利用角解析光電子能譜儀(Angle-resolved photoemission spectroscopy, ARPES)和低能量電子繞射儀 (Low energy electron diffraction, LEED)系統來分析，再搭配理論計算的結果，最後提出新表面態的生成條件及原因。

Previous studies on PbAu surface alloy have revealed an anomalous parabolic band centered at the surface zone boundary 𝑀̅ at the energy ~ —2 eV, with 22 eV. However, such a parabolic band could not be reproduced in theoretical calculation based on the surface alloy model. Therefore we thought this band didn’t originate from the surface alloy.
We suspect that this parabolic band is derived from the surface state of Pb(111), induced from the coupling from Au’s 5d orbital and Pb’s 6p orbital. Therefore, to confirm this idea we deposit Au atoms on Pb(111) single crystal at extremely low temperature to avoid the formation of surface alloy, and then measure the resulting surface states around 𝑀̅ within Pb bulk bang gap.
In the research presented in this thesis, we show a new method to induced new surface states around 𝑀̅ in Pb(111) by the adsorption of Au on Pb(111), and studied them with Angle-resolved photoemission spectroscopy(ARPES) and Low energy electron diffraction(LEED) system, combined with first-principles theoretical calculation. Finally we reach the conclusion about the interesting status and properties of these surface states.

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