Encapsulated Nanowires: Boosting Electronic Transport in Carbon   Nanotubes
  The electrical conductivity of metallic carbon nanotubes (CNTs) quickly saturates with respect to bias voltage due to scattering from a large population of optical phonons. Decay of these dominant scatterers in pristine CNTs is too slow to offset an increased generation rate at high voltage bias. We demonstrate from first principles that encapsulation of 1D atomic chains within a single-walled CNT can enhance decay of "hot" phonons by providing additional channels for thermalisation. Pacification of the phonon population growth reduces electrical resistivity of metallic CNTs by 51% for an example system with encapsulated beryllium. 
Andrij Vasylenko, Jamie Wynn, Paulo Medeiros, Andrew J. Morris, Jeremy   Sloan, David Quigley
cond-mat.mtrl-sci cond-mat.mes-hall