Hysteresis in Random-field Ising model on a Bethe lattice with a mixed coordination number

We study zero-temperature hysteresis in the random-field Ising model on a Bethe lattice where a fraction $c$ of the sites have coordination number $z=4$ while the remaining fraction $1-c$ have $z=3$. Numerical simulations as well as probabilistic methods are used to show the existence of critical hysteresis for all values of $c > 0$. This extends earlier results for $c=0$ and $c=1$ to the entire range $0 \le c \le 1$, and provides new insight in non-equilibrium critical phenomena.