Abstract

We developed a unique model for exciton in monolayer medium with an effective dielectric constant \(\epsilon _{eff}\) (in which the monolayer material is placed on a substrate such as fused silica glass or \(SiO_{2}\) in experiments). Our model was based on an exact solution of the corresponding fully-covariant two-body Dirac-Coulomb type equation. For singlet quantum state of a static electron-hole pair in such a medium, we obtained a non-perturbative frequency spectrum composed of real and imaginary parts. We obtained explicit expressions for practical calculations of binding energy and decaytime of such a system. The results show that one can actively tune both binding energy and decaytime of an exciton during photo-excitation experiments by adjusting the value of \(\epsilon _{eff}\). We think that our calculations and approaches eliminate cross-talk in the literature and explain the discrepancy between experimental results of binding energy of an exciton for different substrates.

Graphic Abstract

中文翻译：

---

介质中激子的结合能和衰减时间

摘要

我们开发了具有有效介电常数\（\ epsilon _ {eff} \）（在其中将单层材料放置在诸如熔融石英玻璃或\（SiO_ {2} \）的基底上的单层介质中激子的独特模型。在实验中）。我们的模型基于相应的全协变二体Dirac-Coulomb型方程的精确解。对于这种介质中的静态电子-空穴对的单重态，我们获得了由实部和虚部组成的非扰动频谱。我们获得了用于该系统的结合能和衰减时间的实用计算的显式表达式。结果表明，在光激发实验中，可以通过调节的值来主动调节激子的结合能和衰减时间。\（\ epsilon _ {eff} \）。我们认为我们的计算和方法消除了文献中的串扰，并解释了激子对不同底物的结合能的实验结果之间的差异。

图形摘要