Quasi-one-dimensional superfluidity in Bose systems
Annotatsiya
The theory of superfluidity of bosons in narrow channels forming a network in space is constructed. It is shown that the temperature Tc of superfluidity transition, below which the system has a long-range order, is equal to h2n/Ml in order of magnitude (here, n is the one-dimensional density of bosons of mass M and l the characteristic length of a link in the network). A generalization of the Ginzburg–Gross–Pitaevskii (GGP) equation permitting an analysis of the decay of current state is proposed. The relaxation time τ for the current state at T > Tc is estimated. It is shown that for a flow velocity υ→0, the relaxation time τ ∝ exp (ħnc/T), where c is the velocity of sound. For ħnc ≫ T ≫ Tc, the supercurrent decay time is astronomically large and quasisuperfluidity cannot be distinguished from true superfluidity in spite of the absence of a long-range order.