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Title: Direct Observation of sp-d Exchange Interactions in Colloidal Mn2+- and Co2+-Doped CdSe Quantum Dots

Abstract

The defining attribute of a diluted magnetic semiconductor (DMS) is the existence of dopant-carrier magnetic exchange interactions. In this letter, we report the first direct observation of such exchange interactions in colloidal doped CdSe nanocrystals. Doped CdSe quantum dots were synthesized by thermal decomposition of (Me4N)2[Cd4(SePh)10] in the presence of TMCl2 (TM2+ ) Mn2+ or Co2+) in hexadecylamine and were characterized by several analytical and spectroscopic techniques. Using magnetic circular dichroism spectroscopy, successful doping and the existence of giant excitonic Zeeman splittings in both Mn2+- and Co2+-doped wurtzite CdSe quantum dots are demonstrated unambiguously.

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1012310
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters, 7(4):1037-1043; Journal Volume: 7; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 77 NANOSCIENCE AND NANOTECHNOLOGY; EXCHANGE INTERACTIONS; MAGNETIC CIRCULAR DICHROISM; MAGNETIC SEMICONDUCTORS; PYROLYSIS; QUANTUM DOTS; SPECTROSCOPY; Environmental Molecular Sciences Laboratory

Citation Formats

Archer, Paul I., Santangelo, Steven A., and Gamelin, Daniel R. Direct Observation of sp-d Exchange Interactions in Colloidal Mn2+- and Co2+-Doped CdSe Quantum Dots. United States: N. p., 2007. Web. doi:10.1021/nl0702362.
Archer, Paul I., Santangelo, Steven A., & Gamelin, Daniel R. Direct Observation of sp-d Exchange Interactions in Colloidal Mn2+- and Co2+-Doped CdSe Quantum Dots. United States. doi:10.1021/nl0702362.
Archer, Paul I., Santangelo, Steven A., and Gamelin, Daniel R. Fri . "Direct Observation of sp-d Exchange Interactions in Colloidal Mn2+- and Co2+-Doped CdSe Quantum Dots". United States. doi:10.1021/nl0702362.
@article{osti_1012310,
title = {Direct Observation of sp-d Exchange Interactions in Colloidal Mn2+- and Co2+-Doped CdSe Quantum Dots},
author = {Archer, Paul I. and Santangelo, Steven A. and Gamelin, Daniel R.},
abstractNote = {The defining attribute of a diluted magnetic semiconductor (DMS) is the existence of dopant-carrier magnetic exchange interactions. In this letter, we report the first direct observation of such exchange interactions in colloidal doped CdSe nanocrystals. Doped CdSe quantum dots were synthesized by thermal decomposition of (Me4N)2[Cd4(SePh)10] in the presence of TMCl2 (TM2+ ) Mn2+ or Co2+) in hexadecylamine and were characterized by several analytical and spectroscopic techniques. Using magnetic circular dichroism spectroscopy, successful doping and the existence of giant excitonic Zeeman splittings in both Mn2+- and Co2+-doped wurtzite CdSe quantum dots are demonstrated unambiguously.},
doi = {10.1021/nl0702362},
journal = {Nano Letters, 7(4):1037-1043},
number = 4,
volume = 7,
place = {United States},
year = {Fri Mar 23 00:00:00 EDT 2007},
month = {Fri Mar 23 00:00:00 EDT 2007}
}
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