Coupling Near-Infrared Emission from Semiconducting Single-Walled Carbon Nanotubes to Optical Microcavities*

Semiconducting single-walled carbon nanotubes (SWCNTs) possess excellent photostability, conductivity, and natural compatibility with nano-/macro-fabrication techniques, making them promising candidates for optoelectronic applications. In particular, their diameter- and chirality-tunable optical transitions at near-infrared wavelengths render them well suited for high-speed optical communication and biomedical imaging applications. Recent demonstrations of chemical modification-induced molecular defects on SWCNT provide another promising avenue for tuning their wavelength coverage further. In this work, we integrate pristine and chemically functionalized SWCNTs into photonic microcavities. By optimizing the cavity-SWCNT coupling geometry, Purcell effect-induced photoluminescence enhancement can be obtained. Compared to pristine SWCNTs, those functionalized with molecular defects exhibit superior emission properties. The generation of stimulated emission in the cavity-SWCNT systems is also investigated through pump-power dependent spectroscopic measurements. This work suggests that due to the natural compatibility of the SWCNTs with photonic structures, local photonic density modification could be an effective approach for optimizing the emission properties of the SWCNTs.