Stability of trions in coupled quantum wells modelled by two-dimensional bilayers

TL;DR

This paper uses quantum Monte Carlo methods to study the stability of trions and biexcitons in ideal 2D bilayer systems, revealing how layer separation affects their binding energies and stability.

Contribution

It provides the first detailed quantum Monte Carlo analysis of indirect trions and biexcitons in 2D bilayers, including the dependence on electron-hole mass ratios.

Findings

Trions become unbound at much larger layer separations than biexcitons.

Critical layer separation varies significantly with electron-hole mass ratio.

Quantum Monte Carlo effectively models Coulomb interactions in 2D bilayer systems.

Abstract

We report variational and diffusion quantum Monte Carlo calculations of the binding energies of indirect trions and biexcitons in ideal two-dimensional bilayer systems within the effective-mass approximation, and with a Coulomb $1/r$ interaction between charge carriers. The critical layer separation at which trions become unbound has been studied for various electron-hole mass ratios, and found to be over an order of magnitude larger than the critical layer separation for biexcitons.