RT Journal Article
T1 Microcanonical finite-size scaling in second-order phase transitions with diverging specific heat
A1 Fernández Pérez, Luis Antonio
A1 Gordillo Guerrero, A.
A1 Martín Mayor, Víctor
A1 Ruiz Lorenzo, J. J.
AB A microcanonical finite-size ansatz in terms of quantities measurable in a finite lattice allows extending phenomenological renormalization  the so-called quotients method to the microcanonical ensemble. The ansatz is tested numerically in two models where the canonical specific heat diverges at criticality, thus implying Fisher renormalization of the critical exponents: the three-dimensional ferromagnetic Ising model and the two-dimensional four-state Potts model (where large logarithmic corrections are known to occur in the canonical ensemble). A recently proposed microcanonical cluster method allows simulating systems as large as L = 1024  Potts or L= 128 (Ising). The quotients method provides accurate determinations of the anomalous dimension, η, and of the (Fisher-renormalized) thermal ν exponent. While in the Ising model the numerical agreement with our theoretical expectations is very good, in the Potts case, we need to carefully incorporate logarithmic corrections to the microcanonical ansatz in order to rationalize our data.
PB American Physical Society
SN 1539-3755
YR 2009
FD 2009-11-06
LK https://hdl.handle.net/20.500.14352/45061
UL https://hdl.handle.net/20.500.14352/45061
LA eng
NO © 2009 The American Physical Society. We have been partly supported through Research Contracts No. FIS2006-08533-C03, No. FIS2007-60977  MICINN, Spain, and No. GR58/08, 910383  Banco de Santander-UCM. The simulations for this work were performed at BIFI.
NO Ministerio de Ciencia e Innovación (MICINN)
NO Banco de Santander-UCM
DS Docta Complutense
RD 23 abr 2025