Spectroscopy and carrier dynamics in CdSe self-assembled quantum dots embedded in ZnxCdyMg1−x−ySe

Authors

G. Comanescu, City University of New York
W. B. Wang, City University of New York
S. Gundry, City University of New York
B. Das, City University of New York
R. R. Alfano, City University of New YorkFollow
M. N. Perez-Paz, City College and Graduate Center of the City University of New York
M. C. Tamargo, Department of Chemistry, City College and Graduate Center of the City University of New York
M. Muñoz, Virginia Commonwealth University
I. Popov, Department of Chemistry, City College and Graduate Center of the City University of New York
L. L. Isaacs, Department of Chemistry, City College and Graduate Center of the City University of New York

Document Type

Article

Original Publication Date

2005

Journal/Book/Conference Title

Applied Physics Letters

Volume

86

Issue

25

DOI of Original Publication

10.1063/1.1947909

Comments

Originally published at http://dx.doi.org/10.1063/1.1947909

Date of Submission

April 2015

Abstract

Time-resolved and steady-state photoluminescence,reflectivity, and absorption experiments were performed on CdSequantum dots in ZnxCdyMg1−x−ySe barriers. Studies of the capture times of the photoexcited carriers into the quantum dots and of electron-hole recombination times inside the dots were performed. Photoluminescence rise time yielded capture times from 20 ps to 30 ps. All samples exhibit fast and slow photoluminescence decays, consistent with observing two independent but energetically overlapping decays. The faster relaxation times for the sample emitting in the blue range is 90 ps, whereas for the two samples emitting in the green it is 345 ps and 480 ps. The slower relaxation times for the sample emitting in blue is 310 ps, whereas for the samples emitting in green is 7.5 ns. These results are explained on the basis of the structural differences among the quantum-dot samples.

Is Part Of

VCU Physics Publications