# Trion and Biexciton in Monolayer Transition Metal Dichalcogenides

## TL;DR

This paper investigates the properties of trions and biexcitons in monolayer transition metal dichalcogenides using a hyperspherical harmonics approach to solve the Schrödinger equations with the Keldysh potential.

## Contribution

It introduces a nonrelativistic potential model with hyperspherical harmonics to accurately compute trion and biexciton energies in monolayer TMDs.

## Key findings

- Ground state energies agree with previous calculations.
- Results align with experimental measurements.
- Method effectively models few-body states in 2D materials.

## Abstract

We study the trion and biexciton in transition metal dichalcogenides monolayers within the framework of a nonrelativistic potential model using the method of hyperspherical harmonics (HH). We solve the three- and four-body Schr\"odinger equations with the Keldysh potential by expanding the wave functions of a trion and biexciton in terms of the antisymmetrized HH. Results of the calculations for the ground state energies are in good agreement with similar calculations for the Keldysh potential and in reasonable agreement with experimental measurements of trion and biexciton binding energies.