Hamiltonian equation of motion and depinning phase transition in two-dimensional magnets
1 Department of Physics, Zhejiang University - Hangzhou 310027, PRC
2 Department of Physics, Hangzhou Normal University - Hangzhou 310036, PRC
Received: 12 June 2012
Accepted: 6 August 2012
Based on the Hamiltonian equation of motion of the ϕ4 theory with quenched random fields, we study the depinning phase transition of the domain-wall motion in two-dimensional magnets. With the short-time dynamic approach, we numerically determine the transition field and critical exponents. The results show that the fundamental Hamiltonian equation of motion belongs to a universality class very different from those effective equations of motion.
PACS: 64.60.Ht – Dynamic critical phenomena
© EPLA, 2012