# MOVPE growth, transmission electron microscopy and magneto-optical spectroscopy of individual InAsP/GaInP quantum dots

## TL;DR

This study investigates the growth, structural properties, and magneto-optical characteristics of individual InAsP/GaInP quantum dots with varying arsenic content, revealing their core-cap structure and carrier confinement behavior.

## Contribution

It provides detailed structural and optical characterization of InAsP/GaInP quantum dots, including core-cap structure and g-factor dependence, advancing understanding of their electronic properties.

## Key findings

- Quantum dots emit from 1.3 to 1.8 eV, confirming As incorporation.
- Core-cap structure with an InAs-rich core and InP-rich cap observed.
- Heavy hole g-factor varies with As molar fraction, indicating type-II confinement.

## Abstract

We report on growth and characterization of individual InAsP/GaInP quantum dots with variable nominal As molar fraction. Magneto-photoluminescence experiments reveal QD emission in a wide range from 1.3 to 1.8 eV confirming incorporation of As into quantum dots. Transmission electron microscopy reveals a core-cap structure of InAsP quantum dots with an InAs-rich core capped by an InP-rich layer. Inside the core, an As molar fraction up to x=0.12 is observed. The heavy hole g-factor is found to be strongly dependent on As molar fraction, while the electron g-factor is close to the InP values. This suggests type-II carrier confinement in the studied InAsP dots with holes (electrons) localized in the core (cap) region. Finally, dynamic nuclear polarization is observed which allows for further insight into structural properties using nuclear magnetic resonance.