title: Vortex state in double transition superconductors.
abstract: The novel vortex phase and nature of the double transition field are investigated by two-component Ginzburg-Landau theory in a situation where fourfold-twofold symmetric superconducting double transition occurs. The deformation from 60 degrees triangular vortex lattice and a possibility of the vortex sheet structure are discussed. In the presence of the gradient coupling, the transition changes to a crossover at finite field. These characters are important to identify the multiple superconducting phase in PrOs4Sb12.
authors.affiliation: Department of Physics, Okayama University, Okayama 700-8530, Japan. matsunaga@mp.okayama-u.ac.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Matsunaga
authors.forename: Masanori
authors.initials: M
authors.lastname: Ichioka
authors.forename: Kazushige
authors.initials: K
authors.lastname: Machida