Critical Behavior of the Ising Model under an external shear field: The Conserved Case

G. P. SARACCO; G. GONNELLA

Conferencia; Statistical Physics of Complex Systems; 2021

The  non-equilibrium  phase  transitions  of  the  two-dimensional  magnetization-conserved Ising model under the action of an external shear field is investigated. This field simulates  a  convective  velocity  profile  with  shear  rate  γ, introduces anisotropic  effects  the  system  evolves  into  non  equilibrium  states.  By employing  short-time dynamics (STD), it was possible to detect first-and  second-order  phase  transitions,  and  in  this  last  case  the  critical  exponent  werecalculated.  If  |M|=0,  the  model  undergoes  a second-order  phase  transition.  The  estimated  critical  temperature  Tc  depends  on γ and  two  regimes  can  be  distinguished:  a  power-law  regime  for  low  γ?s  and  a saturation  regime  at  larger  values  of  it.  For  the  investigated  shear  field  interval,  the estimated values of the anisotropic critical exponents suggest that the critical behavior is on a crossover between the Ising and mean-field critical behaviors, respectively. On the  other  hand  if  |M|>  0,  the  model  exhibits  for  each  γ  first-order  phase  transitions, ending in a critical point at |M|=0.