ar X iv : c on d - m at / 9 50 40 60 v 1 1 3 A pr 1 99 5 A Numerical Study of Phase Transitions Inside the Pores
نویسندگان
چکیده
Phase transitions inside the pores of an aerogel are investigated by modelizing the aerogel structure by diffusion-limited cluster-cluster aggregation on a cubic lattice in a finite box and considering q-states Potts variables on the empty sites interacting via nearest-neighbours. Using a finite size scaling analysing of Monte-Carlo numerical results, it is concluded that for q = 4 the transition changes from first order to second order as the aerogel concentration (density) increases. Comparison is made with the case q = 3 (where the first order transition is weaker in three dimensions) and with the case q = 4 but for randomly (non correlated) occupied sites. Possible applications to experiments are discussed. PACS numbers: 64.60-Ak, 05.50-Fh, 75.40-Mg Typeset using REVTEX a short report of this work has been published in Phys. Rev. Lett. 74, 422 (1995). 1
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