Carrier-dopant exchange interactions in Mn-doped PbS colloidal quantum dots were studied by circularly polarized magneto-photoluminescence. Mn substitutional doping leads to paramagnetic behavior down to 5 K. While undoped quantum dots show negative circular polarization, Mn doping changes its sign to positive. A circular polarization value of 40% was achieved at T=7 K and B=7 tesla. The results are interpreted in terms of Zeeman splitting of the band edge states in the presence of carrier-dopant exchange interactions that are qualitatively different from the s,p-d exchange interactions in II-VI systems.
@article{arxiv.1208.0750,
title = {Carrier-Dopant Exchange Interactions in Mn-doped PbS Colloidal Quantum Dots},
author = {Gen Long and Biplob Barman and Savas Delikanli and Yu Tsung Tsai and Peihong Zhang and Athos Petrou and Hao Zeng},
journal= {arXiv preprint arXiv:1208.0750},
year = {2016}
}
Comments
4 pages, 4 figures; To appear in Applied Physics Letters 101 (2012)