Electronic transport through bent carbon nanotubes: Nanoelectromechanical sensors and switches

We theoretically investigate the mechanical deformations of armchair, zigzag, and zigzag-armchair kink nanotube structures, under severe bendings, within a tight-binding model. It is shown that the zigzag tube is stiffer than the armchair tube with the same diameter. The kink structure is found to be quite stable under severe bendings. Calculating the I-V characteristics, we show that, at the same bias, the current of metallic tube decreases with increased bending, while that of semiconducting tube increases. Such a universal behavior is not observed for the kink structure due to two competing effects. Possible application to nanoelectromechanical sensors and switches is discussed.