Exciton–Phonon Interactions and Temperature Behavior of Optical Spectra in Core/Shell InP/ZnS Quantum Dots

2020 ◽  
pp. 165-196
Author(s):  
Sergey Savchenko ◽  
Alexander Vokhmintsev ◽  
Ilya Weinstein
Keyword(s):  
Quantum Dots ◽  
Optical Spectra ◽  
Temperature Behavior ◽  
Core Shell

High-Temperature Synthesis of CdSe-Based Core/Shell, Core/Shell/Shell, and Core/Graded-Shell Nanoplatelets for Stable and Efficient Narrowband Emitters

2019 ◽  
Author(s):  
Aurelio A. Rossinelli ◽  
Henar Rojo ◽  
Aniket S. Mule ◽  
Marianne Aellen ◽  
Ario Cocina ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Temperature ◽  
Equilibrium Shape ◽  
Size Variation ◽  
Crystal Defects ◽  
Atomic Scale ◽  
Quantum Yields ◽  
Core Shell ◽  
Compositional Gradient ◽  
High Quality

<div>Colloidal semiconductor nanoplatelets exhibit exceptionally narrow photoluminescence spectra. This occurs because samples can be synthesized in which all nanoplatelets share the same atomic-scale thickness. As this dimension sets the emission wavelength, inhomogeneous linewidth broadening due to size variation, which is always present in samples of quasi-spherical nanocrystals (quantum dots), is essentially eliminated. Nanoplatelets thus offer improved, spectrally pure emitters for various applications. Unfortunately, due to their non-equilibrium shape, nanoplatelets also suffer from low photo-, chemical, and thermal stability, which limits their use. Moreover, their poor stability hampers the development of efficient synthesis protocols for adding high-quality protective inorganic shells, which are well known to improve the performance of quantum dots. <br></div><div>Herein, we report a general synthesis approach to highly emissive and stable core/shell nanoplatelets with various shell compositions, including CdSe/ZnS, CdSe/CdS/ZnS, CdSe/Cd<sub>x</sub>Zn<sub>1–x</sub>S, and CdSe/ZnSe. Motivated by previous work on quantum dots, we find that slow, high-temperature growth of shells containing a compositional gradient reduces strain-induced crystal defects and minimizes the emission linewidth while maintaining good surface passivation and nanocrystal uniformity. Indeed, our best core/shell nanoplatelets (CdSe/Cd<sub>x</sub>Zn<sub>1–x</sub>S) show photoluminescence quantum yields of 90% with linewidths as low as 56 meV (19.5 nm at 655 nm). To confirm the high quality of our different core/shell nanoplatelets for a specific application, we demonstrate their use as gain media in low-threshold ring lasers. More generally, the ability of our synthesis protocol to engineer high-quality shells can help further improve nanoplatelets for optoelectronic devices.</div>

Enhanced Photocurrent Generation in Proton‐Irradiated “Giant” CdSe/CdS Core/Shell Quantum Dots

2019 ◽  
Vol 29 (46) ◽  
pp. 1904501 ◽  
Author(s):  
Chao Wang ◽  
David Barba ◽  
Gurpreet S. Selopal ◽  
Haiguang Zhao ◽  
Jiabin Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Core Shell ◽  
Photocurrent Generation

Surface Organic Ligands-Passivated Quantum Dots: Toward High-Performance Light-Emitting Diodes with Long Lifetime

2021 ◽  
Author(s):  
Lishuang Wang ◽  
Ying Lv ◽  
Jie Lin ◽  
Jialong Zhao ◽  
Xingyuan Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Performance ◽  
Light Emitting Diodes ◽  
Organic Ligands ◽  
Colloidal Quantum Dots ◽  
Core Shell ◽  
Light Emitting ◽  
Long Lifetime

For quantum dots light-emitting diodes (QLEDs), typical colloidal quantum dots (QDs) are usually composed of a core/shell heterostructure which is covered with organic ligands as surface passivated materials to confine...

Single-charge transport through hybrid core–shell Au-ZnS quantum dots: a comprehensive analysis from a modified energy structure

Nanoscale ◽  
2021 ◽  
Author(s):  
Tuhin Shuvra Basu ◽  
Simon Diesch ◽  
Ryoma Hayakawa ◽  
Yutaka Wakayama ◽  
Elke Scheer
Keyword(s):  
Quantum Dots ◽  
Electronic Structure ◽  
Carrier Transport ◽  
Comprehensive Analysis ◽  
Energy Structure ◽  
Core Shell ◽  
Single Charge ◽  
Scanning Tunnelling Microscope ◽  
Single Carrier ◽  
Scanning Tunnelling

We examined the modified electronic structure and single-carrier transport of individual hybrid core–shell metal–semiconductor Au-ZnS quantum dots using a scanning tunnelling microscope.

Fabrication of hybrid Pd@Ag core-shell and fully alloyed bi-metallic AgPd NPs and SERS enhancement of Rhodamine 6G by a unique mixture approach with graphene quantum dots

2021 ◽  
Vol 548 ◽  
pp. 149252
Author(s):  
Sanchaya Pandit ◽  
Sundar Kunwar ◽  
Rakesh Kulkarni ◽  
Rutuja Mandavka ◽  
Shusen Lin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Rhodamine 6G ◽  
Graphene Quantum Dots ◽  
Core Shell ◽  
Sers Enhancement

Decoupling and Coupling of the Host–Dopant Interaction by Manipulating Dopant Movement in Core/Shell Quantum Dots

2020 ◽  
Vol 11 (15) ◽  
pp. 5992-5999 ◽  
Author(s):  
Elan Hofman ◽  
Alex Khammang ◽  
Joshua T. Wright ◽  
Zhi-Jun Li ◽  
Peter Francis McLaughlin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Core Shell
Sign in / Sign up

Export Citation Format

Share Document