R Gersch et al 2006 New J. Phys. 8 320 doi:10.1088/1367-2630/8/12/320
R Gersch1,3, J Reiss1 and C Honerkamp2
Show affiliationsFirst-order phase transitions in many-fermion systems are not detected in the susceptibility analysis of common renormalization-group (RG) approaches. Here, we introduce a counterterm technique within the functional renormalization-group (fRG) formalism which allows access to all stable and metastable configurations. It becomes possible to study symmetry-broken states which occur through first-order transitions as well as hysteresis phenomena. For continuous transitions, the standard results are reproduced. As an example, we study discrete-symmetry breaking in a mean-field model for a commensurate charge-density wave. An additional benefit of the approach is that away from the critical temperature for the breaking of discrete symmetries large interactions can be avoided at all RG scales.
05.10.Cc Renormalization group methods
Issue 12 (December 2006)
Received 21 September 2006
Published 14 December 2006
R Gersch et al 2006 New J. Phys. 8 320
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