Phase slip in mesoscopic charge-density-wave systems

Collective electron transport in mesoscopic charge-density-wave (CDW) syste ms is studied theoretically. Sliding motion of the CDW is accompanied by th ermally activated phase-slip processes near electrical contacts. Each phase -slip event gives rise to an addition or removal of a wavefront, resulting in deformation of the overall phase profile. Since the energy barrier for t hermal nucleation of phase-slip centers strongly depends on the phase profi le, its deformation affects the phase-slip rate, particularly in small samp les. We calculate the nonlinear behavior between the CDW current and the ph ase-slip voltage V-ps, taking account of the small-size effect on the phase -slip rate. Using the parameters for NbSe3, we find that the small-size eff ect reduces V-ps when the sample length is smaller than a few micrometers. This behavior is consistent with the recent experiment by Mantel et al.: Ph ys. Rev. Lett. 84 (2000) 538 for mesoscopic NbSe3 wires.