Electric-field-directed growth of aligned single-walled carbon nanotubes

Electric-field-directed growth of single-walled carbon nanotubes by chemical-vapor deposition is demonstrated. The field-alignment effect originates from the high polarizability of single-walled nanotubes. Large induced dipole moments lead to large aligning torques and forces on the nanotube, and prevent randomization of nanotube orientation by thermal fluctuations and gas flows. The results shall open up possibilities in directed growth of ordered molecular-wire architectures and networks on surfaces.