Binding energies of excitonic complexes in type-II quantum rings from diffusion quantum Monte Carlo calculations

Abstract

Excitonic complexes in type-II quantum-ring heterostructures may be considered as artificial atoms due to the confinement of only one charge-carrier type in an artificial nucleus. Binding energies of excitons, trions, and biexcitons in these nanostructures are then effectively ionization energies of these artificial atoms. The binding energies reported here are calculated within the effective-mass approximation using the diffusion quantum Monte Carlo method and realistic geometries for gallium antimonide rings in gallium arsenide. The electrons form a halo outside the ring, with very little charge density inside the central cavity of the ring. The de-excitonization and binding energies of the complexes are relatively independent of the precise shape of the ring.

References in corpus (7)

• Energy spectra of quantum rings
• Continuum variational and diffusion quantum Monte Carlo calculations
• Jastrow correlation factor for atoms, molecules, and solids
• Theoretical interpretation of the experimental electronic structure of lens shaped, self-assembled InAs/GaAs quantum dots
• Framework for constructing generic Jastrow correlation factors
• Extended excitons and compact helium-like biexcitons in type-II quantum dots
• Excitonic Mott transition in type-II quantum dots

Cited by in corpus (1)

• Variational and Diffusion Quantum Monte Carlo Calculations with the CASINO Code