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arXiv · hep-lat/9202004

Multicanonical Ensemble: A New Approach to Simulate First-order Phase Transitions

B. A. Berg·T. Neuhaus
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Abstract

Relying on the recently proposed multicanonical algorithm, we present a numerical simulation of the first order phase transition in the 2d 10-state Potts model on lattices up to sizes $100\times100$. It is demonstrated that the new algorithm $lacks$ an exponentially fast increase of the tunneling time between metastable states as a function of the linear size $L$ of the system. Instead, the tunneling time diverges approximately proportional to $L^{2.65}$. Thus the computational effort as counted per degree of freedom for generating an independent configuration in the unstable region of the model rises proportional to $V^{2.3}$, where $V$ is the volume of the system. On our largest lattice we gain more than two orders of magnitude as compared to a standard heat bath algorithm. As a first physical application we report a high precision computation of the interfacial tension.

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B. A. Berg, T. Neuhaus. 1992-04-08. Multicanonical Ensemble: A New Approach to Simulate First-order Phase Transitions. https://doi.org/10.1103/physrevlett.68.9

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