Non-Gaussian effects and multifractality in the Bragg glass

  title={Non-Gaussian effects and multifractality in the Bragg glass},
  author={Andrei A. Fedorenko and Pierre le Doussal and Kay J{\"o}rg Wiese},
  journal={Europhysics Letters},
We study, beyond the Gaussian approximation, the decay of the translational order correlation function for a d-dimensional scalar periodic elastic system in a disordered environment. We develop a method based on functional determinants, equivalent to summing an infinite set of diagrams. We obtain, in dimension , the even n-th cumulant of relative displacements as }^{\text{c}}\simeq {\cal A}_n \ln r$ ?> with , as well as the multifractal dimension xq of the exponential field . As a corollary, we… 
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