Chiral phase transitions: focus driven critical behavior in systems with planar and vector ordering
Pietro Parruccini


Abstract
The critical behavior of $N$-vector spin systems with non-collinear order is analyzed by a six-loop (five-loop) study in three (two) dimensions of an effective $O(N)times O(M)$ Landau-Ginzburg-Wilson Hamiltonian. For the physically relevant cases with $N=2, 3$ and $M=2$ it is shown that the chiral fixed point which governs the critical behavior is a stable focus both in two and three dimensions. It is also shown that the spiral-like approach of the chiral fixed point results in unusual crossover and near critical regimes that may imitate varying critical exponents seen in physical and computer experiments.

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Elenco dei partecipanti al convegno di Bari.

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