Recent developments in single wall carbon nanotube (SWCNT) functionalization chemistry introducing sp³ defect sites via covalent attachment of chemical functional groups have made SWCNTs a promising material system for a variety of technologies. These defect states boost photoluminescence (PL) quantum yields and open new possibilities for SWCNTs as unique photon sources in emerging applications. In 2015, solitary oxygen defect states incorporated onto SWCNTs were shown to serve as room temperature (RT) single photon emitters at ~1300 nm [1]. More recently, this RT single photon emission (SPE) was further extended to cover 1550 nm telecommunication wavelength band via aryl sp³ defect sites in SWCNTs of larger diameters [2]. The SPE of aryl sp³ are also characterized with ultrahigh single-photon purity and enhanced emission stability approaching the shot-noise limit. While these properties make sp³ defects of SWCNTs very promising material of quantum information technology, establishing the functionalized SWCNTs as transformative materials for quantum technologies demands a detailed understanding and control of their fine electronic structure and quantum coherence properties. Aiming to meet this challenge here, we performed single defect magneto-PL optical spectroscopy on sp³ defects of aryl functionalized SWCNT. Our work reveals indications that the defects possess complex excitonic fine structure that may open a route toward manipulating spin and/or angular momentum of the defect bound exciton for quantum information technology applications.

References

[1] X. Ma et al., Nat. Nanotech., 2015, 10, 671.

[2] X. He et al., Nat. Photon., 2017, 11, 577