近年來，過渡金屬硫化物(Transition metal dichalcogenide, TMDCs)，不論在塊材或
薄膜尺度下皆有出色的光學及電子特性，而薄膜尺度下的 TMDC 層數依賴能帶結構也
是被廣泛討論的原因之一。除了塊材和薄膜，值得注意的是，因 TMDC 層跟層之間微
弱的凡德瓦力，使不同材料構築的 TMDC 異質結構成為可能，這將帶給我們更多前所
未有的特性。而異質結構中層跟層的接觸面是造成材料性質變化的關鍵，因此我們的
工作在於研究界面作用對材料能帶結構的影響。我們透過角解析光電子能譜(Angle
Resolved Photoemission Spectroscopy, ARPES)觀察不同層數 PtSe2/PtTe2異質結構的能帶
結構演化，改變下層基板的厚度分析基板對於電子態雜化的影響以及電子態雜化在材
料的範圍。結果表明，PtSe2能帶結構受到 PtTe2基底影響，有著與雙層石墨烯基底不
同的能帶雜化以及能量位移，並且隨著層數變化 PtTe2的電子態多寡有所變化。除此之
外，透過改變上層厚度我們也發現，上層加厚的 PtSe2薄膜改變了異質結構中的能譜權
重，遮蔽了界面的雜化電子態，暗示了異質結構的界面局域性。

Bulk and thin-film transition metal dichalcogenides (TMDCs) have attracted significant
interest in the condensed matter physics community due to their remarkable optical and
electronic properties. Despite the weak van der Waals interaction between layers, TMDC
heterostructures can exhibit novel physical phenomena arising from the specific composition
and interfacial interactions of their constituent layers. Understanding the mechanism of
interlayer coupling is therefore crucial for tuning the electronic properties of these systems.
In this study, we investigate a model heterostructure composed of PtSe2 and PtTe2 with
varying thicknesses, using angle-resolved photoemission spectroscopy (ARPES). Our results
reveal that the electronic band structure of PtSe2 is modified by the underlying PtTe2 substrate
through electronic hybridization, leading to band renormalization and the emergent band
features. These interfacial phenomena show a strong dependence on the thickness of the PtTe2
layer, indicating that the strength of interlayer coupling can be effectively tuned by the
electronic structure of the substrate. Furthermore, we observe a reduction in the spectral
weight of the hybridized states with increasing PtSe2 thickness, suggesting that the emergent
features are localized at the interface.

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