Ab initio many-body calculation of excitons in solid Ne and Ar

TL;DR

This paper presents a first-principles computational study of excitons in solid neon and argon, calculating their energy levels, wave functions, and spectra using many-body techniques, with results matching experimental data.

Contribution

It introduces a comprehensive ab initio approach combining GW and Bethe-Salpeter equations to accurately compute excitonic properties in solid Ne and Ar.

Findings

Exciton energy levels and wave functions agree with experimental data.

Binding energies and splittings of excitons are accurately predicted.

Electron-hole pairs are delocalized over approximately 7 atomic units in solid Ar.

Abstract

Absorption spectra, exciton energy levels and wave functions for solid Ne and Ar have been calculated from first principles using many-body techniques. Electronic band structures of Ne and Ar were calculated using the GW approximation. Exciton states were calculated by diagonalizing an exciton Hamiltonian derived from the particle-hole Green function, whose equation of motion is the Bethe-Salpeter equation. Singlet and triplet exciton series up to n=5 for Ne and n=3 for Ar were obtained. Binding energies and longitudinal-transverse splittings of n=1 excitons are in excellent agreement with experiment. Plots of correlated electron-hole wave functions show that the electron-hole complex is delocalised over roughly 7 a.u. in solid Ar.