Stark effect in nonhydrogenic low-dimensional excitons

Excitons in two dimensions and other low-dimensional semiconductors are known to deviate from simple Wannier model descriptions due to nonlocal dielectric screening. As a consequence, energy levels do not follow a simple hydrogenic Rydberg series. Recently, a Kratzer model including a repulsive core potential has been suggested as an analytically solvable model of nonhydrogenic excitons. We adopt this model to describe both static and dynamic Stark effects in low-dimensional semiconductors. An exact formula for the exciton polarizability valid for arbitrary dimension and core potential is obtained. Moreover, analytical oscillator strengths allow for analyses of the dynamic Stark effect in various dimensions and materials.

Automated summary

Excitons in two dimensions and other low-dimensional semiconductors show deviation from simple Wannier model due to nonlocal dielectric screening. A Kratzer model, incorporating a repulsive core potential, has been proposed as an analytically solvable model for nonhydrogenic excitons. This study utilizes this model to describe static and dynamic Stark effects in low-dimensional semiconductors, providing an exact formula for exciton polarizability and analytical oscillator strengths for analyzing dynamic Stark effect in different dimensions and materials.