Low-threshold laser medium utilizing semiconductor nanoshell quantum dots

Dmitry Porotnikov, Benjamin T. Diroll, Dulanjan Harankahage, Laura Obloy, Mingrui Yang, James Cassidy, Cole Ellison, Emily Miller, Spencer Rogers, Alexander N. Tarnovsky, Richard D. Schaller, Mikhail Zamkov

Research output: Contribution to journalArticlepeer-review

Abstract

Colloidal semiconductor nanocrystals (NCs) represent a promising class of nanomaterials for lasing applications. Currently, one of the key challenges facing the development of high-performance NC optical gain media lies in enhancing the lifetime of biexciton populations. This usually requires the employment of charge-delocalizing particle architectures, such as core/shell NCs, nanorods, and nanoplatelets. Here, we report on a two-dimensional nanoshell quantum dot (QD) morphology that enables a strong delocalization of photoinduced charges, leading to enhanced biexciton lifetimes and low lasing thresholds. A unique combination of a large exciton volume and a smoothed potential gradient across interfaces of the reported CdSbulk/CdSe/CdSshell (core/shell/shell) nanoshell QDs results in strong suppression of Auger processes, which was manifested in this work though the observation of stable amplified stimulated emission (ASE) at low pump fluences. An extensive charge delocalization in nanoshell QDs was confirmed by transient absorption measurements, showing that the presence of a bulk-size core in CdSbulk/CdSe/CdSshell QDs reduces exciton-exciton interactions. Overall, present findings demonstrate unique advantages of the nanoshell QD architecture as a promising optical gain medium in solid-state lighting and lasing applications.

Original languageEnglish
Pages (from-to)17426-17436
Number of pages11
JournalNanoscale
Volume12
Issue number33
DOIs
Publication statusPublished - Sep 7 2020

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint Dive into the research topics of 'Low-threshold laser medium utilizing semiconductor nanoshell quantum dots'. Together they form a unique fingerprint.

Cite this