Percolation methods for disordered quantum Ising models

Petr Dmitrievich Andriushchenko, Konstantin Valentinovich Nefedev

In this paper we consider an approach, which allows the research of order-disorder transitionin lattice systems (with any distribution of the exchange integrals) in the frame of Ising model. Anew order parameters, which can give a description of a phase transitions, are found. The commondefinition of such order parameter is the mean value of percolation cluster size. Percolation clusterincludes spins in ground state. The transition from absolute disorder to correlated phase could bestudied with using of percolation theory methods.

Gesualdo Delfino A

Liang Cao, M. Jeng, Jennifer M. Schwarz

Petr Dmitrievich Andriushchenko, Konstantin Valentinovich Nefedev

In this paper we consider an approach, which allows researching a processes of order-disorder transition in various systems (with any distribution of the exchange integrals signs) in the frame of Ising model. A new order parameters, which can give a description of a phase transitions, are found. The common definition of these order parameters is the mean value of percolation cluster size. Percolation cluster includes spins with given energy. The transition from absolute disorder to correlated phase could be studied with using of percolation theory methods.

José A. Hoyos

The effects of quenched disorder on nonequilibrium phase transitions in the directed percolation universality class are revisited. Using a strong-disorder energy-space renormalization-group method, it is shown that for any amount of disorder the critical behavior is controlled by an infinite-randomness fixed point in the same universality class of the random transverse-field Ising models.

Mina Fasihi, Haley Cole, Lincoln D. Carr +2 more