Vortex sub-lattice melting in a two-component superconductor
Abstract
We consider the vortex matter in a three-dimensional two-component superconductor with individually conserved condensates with different bare phase stiffnesses in a finite magnetic field, such as the projected superconducting state of liquid metallic hydrogen. The ground state is an Abrikosov lattice of {\it composite}, i.e. co-centered, vortices in both order parameters. We investigate quantitatively two novel phase transitions when temperature is increased at fixed magnetic field. {\it i)} A ``vortex sub-lattice melting" phase transition where vortices in the field with lowest phase stiffness ("light vortices") loose co-centricity with the vortices with large phase stiffness ("heavy vortices"), thus entering a liquid state. Remarkably, the structure factor of the light vortex sub-lattice vanishes {\it continuously}. This novel transition, which has no counterpart in one-component superconductors, is shown to be in the \xy universality class. Across this transition, the lattice of heavy vortices {\it remains intact}.
Cite
@article{arxiv.cond-mat/0411031,
title = {Vortex sub-lattice melting in a two-component superconductor},
author = {Eivind Smorgrav and Jo Smiseth and Egor Babaev and Asle Sudbo},
journal= {arXiv preprint arXiv:cond-mat/0411031},
year = {2007}
}
Comments
4 pages, 3 figures. Figure 3 updated. References added. To be published in Physical Review Letters