Solving the Bethe-Salpeter equation on a subspace: Approximations and consequences for low-dimensional materials

Abstract

It is known that the ambient environment can dramatically renormalize the electron excitation energies and the binding energy of the prominent excitons in low-dimensional materials, but the effect of the environment on the energy splitting of the spin-singlet and spin-triplet exciton states is less understood. Here, the authors derive a relationship between the extent of electronic states, the ambient screening, and the electron-hole exchange interaction and show that the singlet-triplet splitting in the energy of the excitons is largely unaffected by the external dielectric environment in quasi-two-dimensional materials.

Topics & Concepts