Optically active cross-band transition in double-walled carbon nanotube and its impact on Raman resonances

Evaluating the Efficiency of Boron Nitride Coating in Single-Walled Carbon-Nanotube-Based 1D Heterostructure Films by Optical Spectroscopy

“…Raman spectroscopy, for example, can accurately estimate the diameters and interlayer distances of DWCNTs by analyzing the radial breathing modes (RBM) , and G modes or probe the metallicity of the layers based on the G line shape or electronic Raman scattering peaks . The exact inner@outer tube combinations of DWCNTs can be identified by inspecting the RBM frequencies and transition energies in the Raman excitation profiles influenced by moiré-induced vibrational coupling , or based on the optical features originating from the intertube transitions in the Rayleigh spectra, , optical absorption spectra and Raman excitation profiles . Alternatively, they can be deduced from inspecting the intertube energy transfer peaks as was shown recently by Erkens et al combining absorption spectroscopy, photoluminescence excitation spectroscopy (PLE), and tunable Raman spectroscopy .…”

“… 18 The exact inner@outer tube combinations of DWCNTs can be identified by inspecting the RBM frequencies and transition energies in the Raman excitation profiles influenced by moiré-induced vibrational coupling 19 , 20 or based on the optical features originating from the intertube transitions in the Rayleigh spectra, 21 , 22 optical absorption spectra and Raman excitation profiles. 23 Alternatively, they can be deduced from inspecting the intertube energy transfer peaks as was shown recently by Erkens et al combining absorption spectroscopy, photoluminescence excitation spectroscopy (PLE), and tunable Raman spectroscopy. 19 Optical spectroscopy has been also successfully employed for investigating more complex 1D vdW structures such as SWCNT@BNNTs based on different SWCNT templates, e.g.…”

Partial quenching of electronic Raman scattering in double-wall carbon nanotubes by interlayer coupling

“…For instance, the VDW coupling was shown to significantly affect the electronic, optical and vibrational properties of double-wall carbon nanotubes (DWCNT) [31], which can be viewed as the simplest 1D VDW structure comprised of two concentric SWCNTs [30]. The electronic VDW coupling modulates the excitonic energies [32] or leads to the appearance of entirely new optical transitions [33][34][35][36], while efficient interlayer energy transfer is proposed to quench the inner layer photoluminescence (PL) [37,73]. On the other hand, the mechanical VDW coupling is responsible for new collective vibrations [10,38] and frequency shifts due to internal pressure [39,40].…”