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arXiv 2307.09083cond-mat.mtrl-sci
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掺杂碳纳米管中的三激子、激子动力学与光谱改变:一种独特的缺陷驱动机制

Trions, Exciton Dynamics and Spectral Modifications in Doped Carbon Nanotubes: A Singular Defect-Driven Mechanism

Klaus H. Eckstein, Pascal Kunkel, Markus Voelckel, Friedrich Schöppler, Tobias Hertel

AI总结:

本研究结合多种光谱与激子输运/盒中粒子模型,揭示掺杂 s-SWNT 中被俘获电荷通过猝灭位点、势垒和三激子态共同调控激子动力学及光谱。

摘要:

掺杂会显著影响半导体单壁碳纳米管(s-SWNTs)的电子和光物理性质。尽管此前研究已经注意到,在掺杂的 s-SWNTs 中,多余载流子会改变光学光谱并加速非辐射激子衰减,但三激子形成、激子动力学与能量学之间直接的机制关联仍不明确。本工作考察了掺杂诱导的非辐射衰减和激子限域对 s-SWNT 光物理的影响。利用光致发光、连续波吸收和泵浦-探测光谱,我们表明,可通过扩散型激子输运模型和盒中粒子模型联合量化被俘获电荷造成的局域化和势垒形成,从而使由这些模型得到的电荷载流子浓度之间形成一一对应关系。本研究强调了外掺抗衡离子的多方面作用:它们俘获电荷以产生猝灭位点、形成阻碍激子运动的势垒,并承载三激子态。这为理解和优化掺杂 SWNT 的光物理性质作出了重要贡献。

英文摘要:

Doping substantially influences the electronic and photophysical properties of semiconducting single-wall carbon nanotubes (s-SWNTs). Although prior studies have noted that surplus charge carriers modify optical spectra and accelerate non-radiative exciton decay in doped s-SWNTs, a direct mechanistic correlation of trion formation, exciton dynamics and energetics remains elusive. This work examines the influence of doping-induced non-radiative decay and exciton confinement on s-SWNT photophysics. Using photoluminescence, continuous-wave absorption, and pump-probe spectroscopy, we show that localization of and barrier formation by trapped charges can be jointly quantified using diffusive exciton transport- and particle-in-the-box models, yielding a one-to-one correlation between charge carrier concentrations derived from these models. The study highlights the multifaceted role of exohedral counterions, which trap charges to create quenching sites, form barriers to exciton movement, and host trion states. This contributes significantly to understanding and optimizing the photophysical properties of doped SWNTs.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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