# Quenched disorder in the contact process on bipartite sublattices

## TL;DR

This paper investigates how different types of quenched disorder affect the phase behavior of the contact process on bipartite lattices, revealing that symmetric disorder destroys sublattice ordering while asymmetric disorder preserves a phase transition.

## Contribution

It provides a comparative analysis of symmetric and asymmetric quenched disorder effects on the contact process with bipartite sublattices, combining mean field and Monte Carlo methods.

## Key findings

- Symmetric disorder eliminates the active asymmetric phase.
- Asymmetric disorder maintains a phase transition between absorbing and active asymmetric phases.
- The universality class depends on the less disordered sublattice.

## Abstract

We study the effects of distinct types of quenched disorder in the contact process (CP) with a competitive dynamics on bipartite sublattices. In the model, the particle creation depends on its first and second neighbors and the extinction increases according to the local density. The clean (without disorder) model exhibits three phases: inactive (absorbing), active symmetric and active asymmetric, where the latter exhibits distinct sublattice densities. These phases are separated by continuous transitions; the phase diagram is reentrant. By performing mean field analysis and Monte Carlo simulations we show that symmetric disorder destroys the sublattice ordering and therefore the active asymmetric phase is not present. On the other hand, for asymmetric disorder (each sublattice presenting a distinct dilution rate) the phase transition occurs between the absorbing and the active asymmetric phases. The universality class of this transition is governed by the less disordered sublattice.