Magnetic effects on nonlinear mechanical properties of a suspended carbon nanotube

We propose a microscopic model for a nanoelectromechanical system made by a radio-frequency driven suspended carbon nanotube (CNT) in the presence of an external magnetic field perpendicular to the current. As a main result, we show that, when the device is driven far from equilibrium, one can tune the CNT mechanical properties by varying the external magnetic ???eld. Indeed, the magnetic ???eld affects the CNT bending mode dynamics inducing an enhanced damping as well as a noise term due to the electronic phase ???uctuations. The quality factor, as observed experimentally, exhibits a quadratic dependence on external magnetic ???eld strength. Finally, CNT resonance frequencies as a function of gate voltage acquire, increasing the magnetic ???eld strength, a peculiar dip-peak structure that should be experimentally observed.