Suppression of exciton dephasing in sidewall-functionalized carbon nanotubes embedded into metallo-dielectric antennas
Suppression of exciton dephasing in sidewall-functionalized carbon nanotubes embedded into metallo-dielectric antennas
复制标题
嵌入金属电介质天线的侧壁功能化碳纳米管中激子失相的抑制
DOI：
10.1039/c8nr03542c
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发表时间：
2018
期刊：
影响因子：
6.7
通讯作者：
Strauf, Stefan
中科院分区：
文献类型：
--
作者：
Shayan, Kamran;He, Xiaowei;Luo, Yue;Rabut, Claire;Li, Xiangzhi;Hartmann, Nicolai F.;Blackburn, Jeffrey L.;Doorn, Stephen K.;Htoon, Han;Strauf, Stefan
单壁碳纳米管的共价功能化是提高激子发射量子产率的有效途径，可以在室温下实现单光子发射。然而，与缺陷相关的E11* 发射的光谱线宽仍然相当宽。在这里，我们系统地研究了已分散与脱氧胆酸钠（DOC）和聚芴（PFO-BPY）的单个单壁碳纳米管的低温激子发射，通过激光蒸发（LV）或CoMoCat技术生长，并与氧以及3，5-二氯苯基团官能化。氧官能化的单壁碳纳米管中的E11激子保持相当宽，具有高达10 meV的线宽，而发现来自3，5-二氯苯官能化的单壁碳纳米管的激子发射窄约一个数量级。在所有情况下，与DOC相比，用PFO-BPy包裹提供了显著更好的防止泵诱导的失相的保护。为了进一步研究激子局域化对泵浦诱导退相的影响，我们将功能化的单壁碳纳米管嵌入金属-介电天线腔中以最大化光收集。我们发现，归因于LV生长的SWCNTs的3，5-二氯苯量子缺陷的E11* 发射的0 D激子可以显示接近分辨率限制的线宽，低至35 μeV。有趣的是，与相同SWCNT中的E11激子相比，这些0 D激子产生3倍抑制的泵浦诱导激子退相。这些发现提供了一个基础，建立一个统一的描述出现的新的光学行为的共价引入的缺陷，分散剂和激子限制在单壁碳纳米管的相互作用，并可能进一步导致实现难以区分的光子从碳纳米管。
Covalent functionalization of single-walled carbon nanotubes (SWCNTs) is a promising route to enhance the quantum yield of exciton emission and can lead to single-photon emission at room temperature. However, the spectral linewidth of the defect-related E11* emission remains rather broad. Here, we systematically investigate the low-temperature exciton emission of individual SWCNTs that have been dispersed with sodium-deoxycholate (DOC) and polyfluorene (PFO-BPy), are grown by laser vaporization (LV) or by CoMoCat techniques and are functionalized with oxygen as well as 3,5-dichlorobenzene groups. The E11 excitons in oxygen-functionalized SWCNTs remain rather broad with up to 10 meV linewidth while exciton emission from 3,5-dichlorobenzene functionalized SWCNTs is found to be about one order of magnitude narrower. In all cases, wrapping with PFO-BPy provides significantly better protection against pump induced dephasing compared to DOC. To further study the influence of exciton localization on pump-induced dephasing, we have embedded the functionalized SWCNTs into metallo-dielectric antenna cavities to maximize light collection. We show that 0D excitons attributed to the E11* emission of 3,5-dichlorobenzene quantum defects of LV-grown SWCNTs can display near resolution-limited linewidths down to 35 μeV. Interestingly, these 0D excitons give rise to a 3-fold suppressed pump-induced exciton dephasing compared to the E11 excitons in the same SWCNT. These findings provide a foundation to build a unified description of the emergence of novel optical behavior from the interplay of covalently introduced defects, dispersants, and exciton confinement in SWCNTs and might further lead to the realization of indistinguishable photons from carbon nanotubes.