偏振拉曼光譜已被廣泛應用於許多二維材料，包括石墨烯和過渡金屬硫化物，特別是使用線偏振光和圓偏振光為激發光。通過計算不同材料受不同偏振入射光影響的拉曼張量，我們可以得知聲子振動模式是如何表現其偏振態。
在這項工作中，單層二硫化鉬被轉移到擁有不同厚度之二氧化矽的矽基板上，以測量偏振拉曼光譜。結果顯示，當被線偏振的入射光激發時，單層二硫化鉬的面內振動(E^')和面外振動(A_1^')模式分別表現出各向同性和線偏振的散射光。同時，當使用圓偏振光作為激發光時,E^'和A_1^'模態則分別表現出旋向交換(helicity-exchange)和旋向守恆(helicity-conserve)的行為。
更重要的是，實驗結果發現單層二硫化鉬的E^'和 A_1^'振動模式在位於純矽基板上時出現與理論模型相異的情形。我們引入了一個強度偏移量來解釋二硫化鉬的聲子與基板之間的耦合效應。此外，還引用了一些與電子-聲子耦合如何影響拉曼強度的偏振態有關的論文，去解釋這種奇特的現象，深入探討層狀二維材料的聲子與光子之間的交互作用，以期提供未來先進材料應用更多重要的基礎與應用。

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