Deposition of carbon nanotubes around microfiber via evanascent light.

Optical devices based on carbon nanotubes (CNTs) have been realized with several fabrication methods in different structures, such as free-space, fiber-end, waveguide, and fiber structures. Most of waveguide- and fiber-type devices utilize evanescent coupling between the guided light and CNT layers, and offer very high optical damage threshold and high third-order nonlinearity. However, the conventional fabrication methods require complicated processes and waste much of CNTs. In this work, we propose and demonstrate CNT deposition around microfibers induced by injecting light through the fibers. This method can area-selectively deposit desired number of CNTs around microfibers, and can be realized by a simple process and setup. We also demonstrate a passively mode-locked fiber laser using a CNT-deposited microfiber as a passive mode-locker.