  We study the interfacial structure, stability, and elastic properties of
composite carbon films containing nanotubes. Our Monte Carlo simulations show
that Van der Waals forces play a vital role in shaping up the interfacial
geometry, producing a curved graphitic wall surrounding the tubes. The most
stable structures are predicted to have intermediate densities, high
anisotropies, and increased elastic moduli compared to pure amorphous carbon
films.
