Tuning radiative lifetimes in semiconductor quantum dots

Bhattacharyya, B and Mukherjee, A and Mahadevu, R and Pandey, A (2021) Tuning radiative lifetimes in semiconductor quantum dots. In: Journal of Chemical Physics, 154 (7).

PDF jou_che_phy_154-7_2021%0A.pdf - Published Version Restricted to Registered users only Download (1MB) | Request a copy

Abstract

Photonic devices stand to benefit from the development of chromophores with tunable, precisely controlled spontaneous emission lifetimes. Here, we demonstrate a method to continuously tune the radiative emission lifetimes of a class of chromophores by varying the density of electronic states involved in the emission process. In particular, we examined the peculiar composition-dependent electronic structure of copper doped CdZnSe quantum dots. It is shown that the nature and density of electronic states involved with the emission process is a function of copper inclusion level, providing a very direct handle for controlling the spontaneous lifetimes. The spontaneous emission lifetimes are estimated by examining the ratios of emission lifetimes to absolute quantum yields and also measured directly by ultrafast luminescence upconversion experiments. We find excellent agreement between these classes of experiments. This scheme enables us to tune spontaneous emission lifetimes by three orders of magnitude from 15 ns to over 7 μs, which is unprecedented in existing lumophores. © 2021 Author(s).

Item Type:	Journal Article
Publication:	Journal of Chemical Physics
Publisher:	American Institute of Physics Inc.
Additional Information:	This copyright of the article is accessible to the American Institute of Physics Inc.
Keywords:	Cadmium alloys; Chromophores; Copper; Electronic states; Electronic structure; Nanocrystals; Photonic devices; Semiconductor alloys; Spontaneous emission; Zinc alloys, Absolute quantum yields; Density of electronic state; Emission lifetime; Emission process; Radiative emissions; Radiative lifetime; Spontaneous emission lifetime; Three orders of magnitude, Semiconductor quantum dots
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	21 Dec 2021 04:57
Last Modified:	21 Dec 2021 04:57
URI:	http://eprints.iisc.ac.in/id/eprint/68184

Actions (login required)

View Item