Condensed Matter Physics, 2005, vol. 8, No. 1(41), p. 59-74, English

Title: High-temperature series expansions for random Potts models
Authors: M.Hellmund (Mathematisches Institut, Universität Leipzig, Augustusplatz 10/11, D-04109 Leipzig, Germany) , W.Janke (Institut für Theoretische Physik, Universität Leipzig, Augustusplatz 10/11, D-04109 Leipzig, Germany)

We discuss recently generated high-temperature series expansions for the free energy and the susceptibility of random-bond q-state Potts models on hypercubic lattices. Using the star-graph expansion technique, quenched disorder averages can be calculated exactly for arbitrary uncorrelated coupling distributions while keeping the disorder strength p as well as the dimension d as symbolic parameters. We present analyses of the new series for the susceptibility of the Ising (q=2) and 4-state Potts model in three dimensions up to the order 19 and 18, respectively, and compare our findings with results from field-theoretical renormalization group studies and Monte Carlo simulations.

Key words: random Potts models, quenched disorder, high-temperature series expansions, effective critical exponents
PACS: 05.50.+q, 64.60.Fr, 75.10.Hk, 75.10.Nr

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