论文标题
在少数电子状态下的嵌入式Si纳米晶体的红外纳米质性质
Infrared nanoplasmonic properties of hyperdoped embedded Si nanocrystals in the few electrons regime
论文作者
论文摘要
使用局部表面等离子体共振（LSPR）作为光学探针，我们证明了嵌入二氧化硅基质中的磷掺杂硅纳米晶体（SINC）中存在游离载体。在半径范围为2.6至5.5 nm之间的小SINC中，与数值模拟耦合的红外光谱研究使我们能够确定以几个原子精度的电活动磷原子的数量。我们证明，LSP共振只能通过每个纳米晶体支撑大约10个自由电子，从而确认了理论预测并探测等离子的集体性质的极限。我们揭示了一种现象，它是嵌入式纳米晶体独有的，出现避免的交叉行为与掺杂的纳米晶体中局部表面等离子体之间的杂交相关联，硅胶晶体和二氧化硅基质响射子模式。最后，对小尺寸状态下的散射时间依赖性与载体密度的仔细分析使我们能够检测到高掺杂剂浓度下新的散射过程的外观。
Using Localized Surface Plasmon Resonance (LSPR) as an optical probe we demonstrate the presence of free carriers in phosphorus doped silicon nanocrystals (SiNCs) embedded in a silica matrix. In small SiNCs, with radius ranging from 2.6 to 5.5 nm, the infrared spectroscopy study coupled to numerical simulations allows us to determine the number of electrically active phosphorus atoms with a precision of a few atoms. We demonstrate that LSP resonances can be supported with only about 10 free electrons per nanocrystal, confirming theoretical predictions and probing the limit of the collective nature of plasmons. We reveal a phenomenon, unique to embedded nanocrystals, with the appearance of an avoided crossing behavior linked to the hybridization between the localized surface plasmon in the doped nanocrystals and the silica matrix phonon modes. Finally, a careful analysis of the scattering time dependence versus carrier density in the small size regime allows us to detect the appearance of a new scattering process at high dopant concentration.
