TY  - JOUR
A1  - Ruffo, Stefano
A1  - Pikovskij, Arkadij
T1  - Finite-size effects in a population of interacting oscillators
N2  - We consider a large population of globally coupled noisy phase oscillators. In the thermodynamic limit N this system exhibits a nonequilibrium phase transition, at which amacroscopic mean field appears. It is shown that for large but finite system size N the system can be described by the noisy Stuart-Landau equation, yielding scaling behavior of statistical characteristics of the macroscopic mean field with N. The predictions of the theory are checked numerically.
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Pikovskij, Arkadij
A1  - Gupta, Shamik
A1  - Teles, Tarcisio N.
A1  - Benetti, Fernanda P. C.
A1  - Pakter, Renato
A1  - Levin, Yan
A1  - Ruffo, Stefano
T1  - Ensemble inequivalence in a mean-field XY model with ferromagnetic and nematic couplings
JF  - Physical review : E, Statistical, nonlinear and soft matter physics
N2  - We explore ensemble inequivalence in long-range interacting systems by studying an XY model of classical spinswith ferromagnetic and nematic coupling. We demonstrate the inequivalence bymapping themicrocanonical phase diagram onto the canonical one, and also by doing the inverse mapping. We show that the equilibrium phase diagrams within the two ensembles strongly disagree within the regions of first-order transitions, exhibiting interesting features like temperature jumps. In particular, we discuss the coexistence and forbidden regions of different macroscopic states in both the phase diagrams.
Y1  - 2014
U6  - https://doi.org/10.1103/PhysRevE.90.062141
SN  - 1539-3755
SN  - 1550-2376
VL  - 90
IS  - 6
PB  - American Physical Society
CY  - College Park
ER  -