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arXiv · 1505.00126

Exposure of the Hidden Anti-Ferromagnetism in Paramagnetic CdSe:Mn Nanocrystals

Shou-Jyun Zou·Sheng-Tsung Wang·Ming-Fan Wu·Wen-Bin Jian·Shun-Jen Cheng
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Abstract

We present theoretical and experimental investigations of the magnetism of paramagnetic semiconductor CdSe:Mn nanocrystals and propose an efficient approach to the exposure and analysis of the underlying anti-ferromagnetic interactions between magnetic ions therein. A key advance made here is the build-up of an analysis method with the exploitation of group theory technique that allows us to distinguish the anti-ferromagnetic interactions between aggregative Mn2+ ions from the overall pronounced paramagnetism of magnetic ion doped semiconductor nanocrystals. By using the method, we clearly reveal and identify the signatures of anti-ferromagnetism from the measured temperature dependent magnetisms, and furthermore determine the average number of Mn2+ ions and the fraction of aggregative ones in the measured CdSe:Mn nanocrystals.

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Shou-Jyun Zou, Sheng-Tsung Wang, Ming-Fan Wu, Wen-Bin Jian, Shun-Jen Cheng. 2015-05-01. Exposure of the Hidden Anti-Ferromagnetism in Paramagnetic CdSe:Mn Nanocrystals. https://doi.org/10.1021/nn5056892

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