title: Strong disorder fixed point in absorbing-state phase transitions.
abstract: The effect of quenched disorder on nonequilibrium phase transitions in the directed percolation universality class is studied by a strong disorder renormalization group approach and by density matrix renormalization group calculations. We show that for sufficiently strong disorder the critical behavior is controlled by a strong disorder fixed point and in one dimension the critical exponents are conjectured to be exact: beta=(3-sqrt[5])/2 and nu( perpendicular )=2. For disorder strengths outside the attractive region of this fixed point, disorder dependent critical exponents are detected. Existing numerical results in two dimensions can be interpreted within a similar scenario.
authors.affiliation: Departement WNI, Limburgs Universitair Centrum, 3590 Diepenbeek, Belgium.
authors.forename: Jef
authors.initials: J
authors.lastname: Hooyberghs
authors.forename: Ferenc
authors.initials: F
authors.lastname: Iglói
authors.forename: Carlo
authors.initials: C
authors.lastname: Vanderzande