Testing Haldane's conjecture in the O(3) model by a Meron cluster simulation
Por:
Bietenholz W., Pochinsky A., Wiese U.-J.
Publicada:
1 ene 1996
Resumen:
Twelve years ago, Haldane formulated his famous conjecture for 1-d antiferromagnetic quantum spin chains. In the context of the 2-d O(3) ? model with ? term, it predicts a phase transition as ? ? ?, which has not yet been verified reliably. To simulate this we use the Wolff cluster algorithm together with an improved estimator for the charge distribution. Each cluster carries integer or half integer charge. Clusters with charge 1/2 are identified with merons. At ? = ? they are inactive, such that the mass gap vanishes. We obtain critical exponents which are consistent with predictions from the k = 1 WZNW model, therefore confirming a second order phase transition.
Filiaciones:
Bietenholz W.:
CTP-LNS, Massachusetts Inst. of Technology, Cambridge, MA 02139, United States
Pochinsky A.:
CTP-LNS, Massachusetts Inst. of Technology, Cambridge, MA 02139, United States
ITEP, B. Cheremushckinskaya 25, 117259 Moscow, Russian Federation
Wiese U.-J.:
CTP-LNS, Massachusetts Inst. of Technology, Cambridge, MA 02139, United States
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