Mechanically induced spin resonance in a carbon nanotube

Abstract

The electron spin is a promising qubit candidate for quantum computation and quantum information. Here we propose and analyze a mechanically induced single electron spin resonance, which amounts to a rotation of the spin about the x axis in a suspended carbon nanotube. The effect is based on the coupling between the spin and the mechanical degree of freedom due to the intrinsic curvature-induced spin-orbit coupling. A rotation about the z axis is obtained by the off-resonant external electric driving field. Arbitrary-angle rotations of the single-electron spin about any axis in the x-z plane can be obtained with a single operation by varying the frequency and the strength of the external electric driving field. With multiple steps combining the rotations about the x and z axes, arbitrary-angle rotations about arbitrary axes can be constructed, which implies that any single-qubit gate of the electron-spin qubit can be performed. We simulate the system numerically by using a master equation with realistic parameters.