Interaction effects in non-Hermitian models of vortex physics
Abstract
Vortex lines in superconductors in an external magnetic field slightly tilted from randomly-distributed parallel columnar defects can be modeled by a system of interacting bosons in a non-Hermitian vector potential and a random scalar potential. We develop a theory of the strongly-disordered non-Hermitian boson Hubbard model using the Hartree-Bogoliubov approximation and apply it to calculate the complex energy spectra, the vortex tilt angle and the tilt modulus of (1+1)-dimensional directed flux line systems. We construct the phase diagram associated with the flux-liquid to Bose-glass transition and find that, close to the phase boundary, the tilted flux liquid phase is characterized by a band of localized excitations, with two mobility edges in its low-energy spectrum.
Cite
@article{arxiv.cond-mat/0101434,
title = {Interaction effects in non-Hermitian models of vortex physics},
author = {Kihong Kim and David R. Nelson},
journal= {arXiv preprint arXiv:cond-mat/0101434},
year = {2009}
}
Comments
19 pages, 19 figures, To appear in Phys. Rev. B