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巨大的刺激性泽曼裂变在合式CO2+合的ZnSe量子点中
Nick S Norberg1, Gregory L Parks, G Mackay Salley
1Department of Chemistry, Box 351700, University of Washington, Seattle, 98195-1700, USA.
Journal of the American Chemical Society
|October 5, 2006
概括
合性-化量子点 (Co(2+):ZnSe DMS-QDs) 显示它们的核心中没有剂. 与散装材料相比,这种无核心的兴奋剂减少了激发性泽曼分裂能量.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 半导体物理 半导体物理
背景情况:
- 稀释的磁性半导体量子点 (DMS-QDs) 提供可调节的电子和磁性特性.
- 了解兴奋剂的结合对于优化DMS-QD性能至关重要.
- 添加化 (Co(2+):ZnSe) 是一个有前途的DMS-QD系统.
研究的目的:
- 为了研究ZnSe量子点中的Co(2+) 的合并部位和光谱特性.
- 分析剂位置对激发性齐曼分裂的影响.
- 为了确定从核心中排除多剂是否是合体DMS-QDs中的一般现象.
主要方法:
- 使用热注射方法制备合式Co2+:ZnSe DMS-QDs.
- 频谱分析包括联体场电子吸收和磁圆二元化 (MCD).
- 时间分辨率吸收光谱法,以追踪合成期间的多潘体积.
主要成果:
- 谱学数据证实了ZnSe QDs中同质的替代性纳入Co ((2+) 的情况.
- 发现剂被排除在中央核心之外,在纳米晶体生长过程中被纳入.
- 兴奋的泽曼分裂能量明显小于预测从大量数据,由于核心剂缺席.
结论:
- 从核化部位中排除多剂是影响 colloidal DMS-QDs 特性的一个关键因素.
- 核心剂的缺失从量上解释了减少的激发性泽曼分裂.
- 提出了一个一般原则:通过直接方法合成的体DMS-QDs将比散装对应物表现出较小的激发性Zeeman分裂.
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