This paper describes a new method to create nanoscale SiO 2 pits or channels using single-walled carbon nanotubes (SWNTs) in an HF solution at room temperature within a few seconds. Using aligned SWNT arrays, a pattern of nanoscale SiO 2 channels can be prepared. The nanoscale SiO 2 patterns can also be created on the surface of three- dimensional (3D) SiO 2 substrate and even the nanoscale trenches can be constructed with arbitrary shapes. A possible mechanism for this enhanced etching of SiO 2 has been qualitatively analysed using defects in SWNTs, combined with H 3 O + electric double layers around SWNTs in an HF solution.
The optical waveguide behaviors of CdS and CdSxSe1?x nanostructures are studied using near-field optical microscopy. Optical measurements demonstrate that light may be guided on sub-wavelength scales along CdS nanoribbons in straight or bent structures. The photoluminescence (PL) spectra from nanoribbon emission using scanning near-field optical microscopy are analyzed under different incident laser intensities. The PL spectra along Se-doped and undoped CdS nanoribbons at different propagation distances are investigated. Both the guided PL spectra of Se-doped and undoped CdS nanoribbons show red-shifts because of the band-edge absorption. Our results are useful for the development of new kinds of functional nano devices.
WANG XiaoLIU DanPAN AnlianFANG ZheyuHUANG ShanZHU Xing
