One-dimensional superfluidity in Bose crystals
Abstract
The possibility of delocalization of particles in a quantum crystal at the nucleus of a dislocation and the transition of delocalized particles into a superfluid state are predicted. A theory is constructed for the one-dimensional superfluidity of a slightly nonideal Bose gas. The effect of impurities on the superfluid density is studied and it is shown that impurities do not destroy the superfluidity, but rather make an additional contribution to the normal component, different from zero even at T = 0. The flow of the superfluid current through a weak link is studied. It is established that in spite of the fact that there is no long-range order in the one-dimensional case, a superfluid current will flow through a weak link without dissipation. Some experimental manifestations of dislocation superfluidity are discussed.