Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2002-08-26
Physics
Condensed Matter
Statistical Mechanics
48 pages, no figures, two typos fixed
Scientific paper
New field theoretic renormalization group methods are developed to describe in a unified fashion the critical exponents of an m-fold Lifshitz point at the two-loop order in the anisotropic (m not equal to d) and isotropic (m=d close to 8) situations. The general theory is illustrated for the N-vector phi^4 model describing a d-dimensional system. A new regularization and renormalization procedure is presented for both types of Lifshitz behavior. The anisotropic cases are formulated with two independent renormalization group transformations. The description of the isotropic behavior requires only one type of renormalization group transformation. We point out the conceptual advantages implicit in this picture and show how this framework is related to other previous renormalization group treatments for the Lifshitz problem. The Feynman diagrams of arbitrary loop-order can be performed analytically provided these integrals are considered to be homogeneous functions of the external momenta scales. The anisotropic universality class (N,d,m) reduces easily to the Ising-like (N,d) when m=0. We show that the isotropic universality class (N,m) when m is close to 8 cannot be obtained from the anisotropic one in the limit d --> m near 8. The exponents for the uniaxial case d=3, N=m=1 are in good agreement with recent Monte Carlo simulations for the ANNNI model.
No associations
LandOfFree
A new picture of the Lifshitz critical behavior does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A new picture of the Lifshitz critical behavior, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A new picture of the Lifshitz critical behavior will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-644152