A simple variational quantum Monte Carlo-effective mass approach for excitons and trions in quantum dots

TL;DR

This paper introduces a simple, efficient variational quantum Monte Carlo method with effective mass Hamiltonians to accurately compute exciton and trion energies in quantum dots, demonstrating strong correlation effects and computational advantages.

Contribution

The paper presents a novel variational quantum Monte Carlo approach combined with effective mass Hamiltonians for excitons and trions in quantum dots, offering improved efficiency and accuracy over existing methods.

Findings

Accurate ground state energies for excitons and trions in quantum dots.

The method outperforms configuration interaction calculations in computational efficiency.

Results agree well with exact variational calculations.

Abstract

A computational model is presented to calculate the ground state energy of neutral and charged excitons confined in semiconductor quantum dots. The model is based on the variational Quantum Monte Carlo method and effective mass Hamiltonians. Through an iterative Newton-Rhapson process, minimizing the local energy, and (optional) parallelization of random walkers, fast and accurate estimates of both confinement and Coulomb binding energies can be obtained in standard desktop computers. To illustrate the reach of the model, we provide Fortran programs and illustrative calculations for colloidal CdSe nanoplatelets with large lateral dimensions and dielectric confinement, where electronic correlations are strong. The results compare well with exact variational calculations and largely outperform configuration interaction calculations in computational efficiency.