Evaluation of localized semiconductor to metal transition of semiconducting carbon nanotube by Tip-enhanced Raman investigation

Tailoring feature of single walled carbon nanotubes (SWNTs) in property by structure deformation has been an interdisciplinary subject of interest for researchers with an expectation that the control of the electronic property will open an access to new world where nano-circuit and nano-actuator exist and it is quit easy. Recently, drastic change of the properties of crossed SWNTs, for example by bridging them over other SWNTs [1], have received widespread attention because a transition from semiconducting state to metallic state was proved to appear only on the junction of crossed semiconducting SWNTs due to π* − σ* hybridization effect, which was theoretically expected since long before [2]. Here, we present a tip-enhanced Raman investigation of extremely localized transition from semiconducting to metal on the junction of crossed SWNTs.