基于可解激子模型的单层过渡金属二卤化物材料参数的解析检索
Analytical Retrieval of Material Parameters in Monolayer Transition-Metal Dichalcogenides Based on a Solvable Exciton Model
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中文总结 AI 辅助
该研究基于可解激子模型开发解析程序，从光学和磁光激子光谱检索单层过渡金属二卤化物材料参数，分两阶段确定相关参数，无需额外拟合或矩阵对角化，应用于多种样品，结果与实验吻合，为二维半导体表征提供有效工具。
中文摘要 AI 辅助
我们基于可解的修正克拉策尔模型，开发了一种从光学和磁光激子光谱中检索单层过渡金属二卤化物基本材料参数的解析程序。该程序自然地由两个互补阶段组成。第一阶段，通过显式反演公式直接从三个最低激子态的实验测量能量确定准粒子带隙、有效屏蔽参数和能量缩放因子，进而得到屏蔽长度。第二阶段，激子能量对磁场依赖性的解析表达式独立给出约化激子质量，从而计算出周围介电常数。一旦检索到完整的材料参数集，该框架无需引入额外拟合参数或进行矩阵对角化，就能解析预测抗磁系数、激子半径和完整的磁激子光谱。我们将该方法应用于嵌入不同介电环境的多种WSe₂、WS₂、MoS₂、MoSe₂和MoTe₂单层实验样品。检索到的材料参数与独立实验测量值和先前的里托娃 - 凯尔迪什（RK）计算结果吻合良好，预测的激子特性准确再现了现有的磁光观测结果。所提出的解析理论为传统数值拟合程序提供了一种高效、物理透明的替代方法，为通过激子光谱快速表征二维半导体提供了有效工具。
英文摘要
We develop an analytical procedure to retrieve fundamental material parameters of monolayer transition-metal dichalcogenides from optical and magneto-optical exciton spectra, based on the solvable modified Kratzer model. The proposed retrieval procedure naturally consists of two complementary stages. In the first stage, explicit inversion formulas determine the quasiparticle bandgap, effective screening parameter, and energy scaling factor directly from the experimentally measured energies of the three lowest excitonic states, from which the screening length is subsequently obtained. In the second stage, an analytical expression for the magnetic-field dependence of the exciton energies independently yields the reduced exciton mass, from which the surrounding dielectric constant is then calculated. Once the complete set of material parameters has been retrieved, the framework analytically predicts the diamagnetic coefficients, exciton radii, and complete magnetoexciton spectra without introducing additional fitting parameters or matrix diagonalization. The method is applied to a broad range of experimental samples for WSe$_2$, WS$_2$, MoS$_2$, MoSe$_2$, and MoTe$_2$ monolayers embedded in different dielectric environments. The retrieved material parameters are in good agreement with independent experimental measurements and previous Rytova--Keldysh (RK) calculations, while the predicted excitonic properties accurately reproduce available magneto-optical observations. The proposed analytical theory provides an efficient, physically transparent alternative to conventional numerical fitting procedures and offers an effective tool for the rapid characterization of two-dimensional semiconductors via excitonic spectroscopy.
