Crafting Core/Graded Shell–Shell Quantum Dots with Suppressed Re‐absorption and Tunable Stokes Shift as High Optical Gain Materials
Abstract
The key to utilizing quantum dots (QDs) as lasing media is to effectively reduce non‐radiative processes, such as Auger recombination and surface trapping. A robust strategy to craft a set of CdSe/Cd1−xZnxSe1−ySy/ZnS core/graded shell–shell QDs with suppressed re‐absorption, reduced Auger recombination rate, and tunable Stokes shift is presented. In sharp contrast to conventional CdSe/ZnS QDs, which have a large energy level mismatch between CdSe and ZnS and thus show strong re‐absorption and a constrained Stokes shift, the as‐synthesized CdSe/Cd1−xZnxSe1−ySy/ZnS QDs exhibited the suppressed re‐absorption of CdSe core and tunable Stokes shift as a direct consequence of the delocalization of the electron wavefunction over the entire QD. Such Stokes shift‐engineered QDs with suppressed re‐absorption may represent an important class of building blocks for use in lasers, light emitting diodes, solar concentrators, and parity‐time symmetry materials and devices.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 15, 2016
- Source ID
- 10.1002/anie.201601198
Entities
People
- Chun Hao Lin
- Edwin L. Thomas
- Jaehan Jung
- Sidney T. Malak
- Valy Vardeny
- Vladimir V. Tsukruk
- Yaxin Zhai
- Young Jun Yoon
- Zhiqun Lin
Organizations
- Air Force Office of Scientific Research
- Georgia Tech
- Rice University
- University of Utah