Quasi-one-dimensional 4He inside carbon nanotubes

Abstract

We report results of diffusion Monte Carlo calculations for both 4He absorbed in a narrow single walled carbon nanotube (R=3.42Å) and strictly one-dimensional 4He. Inside the tube, the binding energy of liquid 4He is approximately three times larger than on planar graphite. At low linear densities, 4He in a nanotube is an experimental realization of a one-dimensional quantum fluid. However, when the density increases the structural and energetic properties of both systems differ. At high density, a quasicontinuous liquid-solid phase transition is observed in both cases.