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Title: Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets

Abstract

We used photoluminescence spectroscopy to resolve two emission features in CdSe/CdMnS/CdS and CdSe/CdS core/multi-shell nanoplatelet heterostructures. The photoluminescence from the magnetic sample has a positive circular polarization with a maximum centered at the position of the lower energy feature. The higher energy feature has a corresponding signature in the absorption spectrum; this is not the case for the low-energy feature. We have also studied the temporal evolution of these features using a pulsed-excitation/time-resolved photoluminescence technique to investigate their corresponding recombination channels. A model was used to analyze the temporal dynamics of the photoluminescence which yielded two distinct timescales associated with these recombination channels. The above results indicate that the low-energy feature is associated with recombination of electrons with holes localized at the core/shell interfaces; the high-energy feature, on the other hand, is excitonic in nature with the holes confined within the CdSe cores.

Authors:
 [1];  [2]; ;  [3];  [4]; ; ; ;  [5]; ;  [1]
  1. Department of Electrical Engineering, State University of New York, University at Buffalo, Buffalo, New York 14260 (United States)
  2. (United States)
  3. LUMINOUS Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Materials Sciences, Nanyang Technological University, Singapore 639798 (Singapore)
  4. (Turkey)
  5. Department of Physics, State University of New York, University at Buffalo, Buffalo, New York 14260 (United States)
Publication Date:
OSTI Identifier:
22590790
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTRA; CADMIUM SELENIDES; CADMIUM SULFIDES; INTERFACES; NANOSTRUCTURES; PHOTOLUMINESCENCE; POLARIZATION; PULSES; RECOMBINATION; SPECTROSCOPY; TIME RESOLUTION

Citation Formats

Murphy, J. R., Department of Physics, State University of New York, University at Buffalo, Buffalo, New York 14260, Delikanli, S., Demir, H. V., E-mail: volkan@bilkent.edu.tr, Department of Electrical and Electronics Engineering, Department of Physics, UNAM−Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Scrace, T., Zhang, P., Norden, T., Petrou, A., E-mail: petrou@buffalo.edu, Thomay, T., and Cartwright, A. N. Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets. United States: N. p., 2016. Web. doi:10.1063/1.4953840.
Murphy, J. R., Department of Physics, State University of New York, University at Buffalo, Buffalo, New York 14260, Delikanli, S., Demir, H. V., E-mail: volkan@bilkent.edu.tr, Department of Electrical and Electronics Engineering, Department of Physics, UNAM−Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Scrace, T., Zhang, P., Norden, T., Petrou, A., E-mail: petrou@buffalo.edu, Thomay, T., & Cartwright, A. N. Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets. United States. doi:10.1063/1.4953840.
Murphy, J. R., Department of Physics, State University of New York, University at Buffalo, Buffalo, New York 14260, Delikanli, S., Demir, H. V., E-mail: volkan@bilkent.edu.tr, Department of Electrical and Electronics Engineering, Department of Physics, UNAM−Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Scrace, T., Zhang, P., Norden, T., Petrou, A., E-mail: petrou@buffalo.edu, Thomay, T., and Cartwright, A. N. 2016. "Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets". United States. doi:10.1063/1.4953840.
@article{osti_22590790,
title = {Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets},
author = {Murphy, J. R. and Department of Physics, State University of New York, University at Buffalo, Buffalo, New York 14260 and Delikanli, S. and Demir, H. V., E-mail: volkan@bilkent.edu.tr and Department of Electrical and Electronics Engineering, Department of Physics, UNAM−Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800 and Scrace, T. and Zhang, P. and Norden, T. and Petrou, A., E-mail: petrou@buffalo.edu and Thomay, T. and Cartwright, A. N.},
abstractNote = {We used photoluminescence spectroscopy to resolve two emission features in CdSe/CdMnS/CdS and CdSe/CdS core/multi-shell nanoplatelet heterostructures. The photoluminescence from the magnetic sample has a positive circular polarization with a maximum centered at the position of the lower energy feature. The higher energy feature has a corresponding signature in the absorption spectrum; this is not the case for the low-energy feature. We have also studied the temporal evolution of these features using a pulsed-excitation/time-resolved photoluminescence technique to investigate their corresponding recombination channels. A model was used to analyze the temporal dynamics of the photoluminescence which yielded two distinct timescales associated with these recombination channels. The above results indicate that the low-energy feature is associated with recombination of electrons with holes localized at the core/shell interfaces; the high-energy feature, on the other hand, is excitonic in nature with the holes confined within the CdSe cores.},
doi = {10.1063/1.4953840},
journal = {Applied Physics Letters},
number = 24,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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