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New Universality Classes for Quantum Critical Behavior

H. Hamidian·G. Semenoff·P. Suranyi·L. C. R. Wijewardhana
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Abstract

We use the epsilon expansion to explore a new universality class of second order quantum phase transitions associated with a four-dimensional Yukawa field theory coupled to a traceless Hermitean matrix scalar field. We argue that this class includes four-fermi models in $2<D<4$ dimensions with $SU(N_F)\times U(N)$ symmetry and a U(N) scalar, $SU(N_F)$ iso-vector 4-fermi coupling. The epsilon expansion indicates that there is a second order phase transition for $N\geq N^*(N_F)$, where $N^*(N_F)\simeq.27N_F$ if $N_F\to\infty$.

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H. Hamidian, G. Semenoff, P. Suranyi, L. C. R. Wijewardhana. 1995-04-27. New Universality Classes for Quantum Critical Behavior. https://doi.org/10.1103/physrevlett.74.4976

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