INVESTIGADORES
CORNETTE valeria cecilia
congresos y reuniones científicas
Título:
Study of stiffness energy on fractals
Autor/es:
CORNETTE V.; NIETO F.; RAMÍREZ-PASTOR A. J.
Lugar:
Los Reyunos, San Rafael, Mendoza, Argentina
Reunión:
Taller; V Taller Regional de Física Estadística y sus Aplicaciones a la Física de la Materia Condensada (TREFEMAC); 2007
Resumen:
The present work focuses on the order-disorder transition of an Ising model on
fractals surface. We present a detailed numerical study, based on the Monte Carlo
method by analyzing the domain-wall energy, of the critical temperature of the Ising
model on some two-dimensional deterministic and non-deterministic fractal lattices
with different Hausdorff dimensions. Those with finite ramification order do not
display ordered phases at any finite temperature, whereas the lattices with infinite
connectivity show genuine critical behavior. The exponent q plays a central role in
the droplet picture. It is usually calculated by using the concept of defect energy,
DF = Fa− Fp, which is the difference between the ground-state (GS) energies for
antiperiodic (Fa) and periodic (Fp) boundary conditions, in one of the directions
of a d-dimensional system of linear size L. In ferromagnetic systems, DF ~ Lq,
with q= ds = d−1, because the induced defect is a (d-1 )-dimensional domain-wall
with all their bonds frustrated. A positive value of the stiffness exponent q (T=0 )
indicates the existence of a phase transition for non-zero temperature. The data
show in a clear way the existence of an order-disorder transition at finite temperature
in this systems.