Nonuniversal Correlations and Crossover Effects in the BraggGlass Phase of Impure Supercon.pdf

Nonuniversal Correlations and Crossover Effects in the Bragg-Glass Phase of Impure Superconductors 1 2 1 Simon Bogner , Thorsten Emig , Thomas Nattermann 1 Institut f¨ur Theoretische Physik, Universit¨at zu K¨oln, Z¨ulpicher Straße 77, D-50937 K¨oln, Germany 0 2Physics Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 0 (February 1, 2008) 0 2 The structural correlation functions of a weakly disordered Abrikosov lattice are calculated in v a functional RG-expansion in d = 4 − ǫ dimensions. It is shown, that in the asymptotic limit o the Abrikosov lattice exhibits still quasi-long-range translational order described by a nonuniversal N exponent ηG which depends on the ratio of the renormalized elastic constants κ = c66/c11 of the flux line (FL) lattice. Our calculations clearly demonstrate three distinct scaling regimes corresponding 9 to the Larkin, the random manifold and the asymptotic Bragg-glass regime. On a wide range of 2 intermediate length scales the FL displacement correlation function increases as a power law with ] twice the manifold roughness exponent ζRM (κ), which is also nonuniversal. Correlation functions n in the asymptotic regime are calculated in their full anisotropic dependencies and various order o parameters