Scattering properties of paramagnetic ground states in the three-dimensional random-field Ising model
School of Physical Sciences, Jawaharlal Nehru University - New Delhi-110067, India
2 Department of Physics, Indian Institute of Technology - Hauz Khas, New Delhi-110016, India
Accepted: 12 September 2011
We study the ground-state (T=0) morphologies in the d=3 random-field Ising model (RFIM) using a computationally efficient graph-cut method. We focus on paramagnetic states which arise for disorder strengths Δ>Δc, where Δc is the critical disorder strength at T=0. These paramagnetic states consist of correlated “domains” of up and down spins which are separated by rough, fractal interfaces. They show novel scattering properties with a cusp singularity in the correlation function at short distances.
PACS: 64.60.De – Statistical mechanics of model systems (Ising model, Potts model, field-theory models, Monte Carlo techniques, etc.) / 68.35.Rh – Phase transitions and critical phenomena / 75.60.Ch – Domain walls and domain structure
© EPLA, 2011