Regensburg 2019 – wissenschaftliches Programm
DY 51.1: Poster
Donnerstag, 4. April 2019, 15:00–18:00, Poster B2
Random Field Ising Model with spatially disorder strength gradient — •Christoph Polle and Alexander K. Hartmann — Institut für Physik, University of Oldenburg, Germany
We study numerically  a three-dimensional Random Field Ising Model (RFIM) in which a spatially disorder strength gradient h(x) is introduced. The gradient was chosen so that h(x) is equal to the critical value hc = 2.28  at the half of the lattice in x-direction. The actual magnetic field acting on a spin i is defined as hi = h(x)*ni, where ni is a (0,1) quenched Gaussian number.
To investigate the system efficiently the RFIM was transformed to a network, then the maximum flow problem was solved to determine the ground state . This is done for different system sizes and realizations. From the ground state the magnetization, a specific-heat like quantity and the susceptibility where calculated as a function of x. Also the system was analyzed in the spirit of gradient percolation problems.
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