Efficient Band-Edge Emission from Indirect Bandgap Semiconductor Quantum Dots upon Shell Engineering.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37022343.
- Also identified by DOI 10.1021/acs.nanolett.3c00008.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Environmentally friendly colloidal quantum dots (QDs) of groups III-V are in high demand for next-generation high-performance light-emitting devices for display and lighting, yet many of them (e.g., GaP) suffer from inefficient band-edge emission due to the indirect bandgap nature of their parent materials. Herein, we theoretically demonstrate that efficient band-edge emission can be activated at a critical tensile strain γ<sub>c</sub> enabled by the capping shell when forming a core/shell architecture. Before γ<sub>c</sub> is reached, the emission edge is dominated by dense low-intensity exciton states with a vanishing oscillator strength and a long radiative lifetime. After γ<sub>c</sub> is crossed, the emission edge is dominated by high-intensity bright exciton states with a large oscillator strength and a radiative lifetime that is shorter by a few orders of magnitude. This work provides a novel strategy for realizing efficient band-edge emission of indirect semiconductor QDs via shell engineering, which is potentially implemented employing the well-established colloidal QD synthesis technique.