Concentration estimates for the isoperimetric constant of the super   critical percolation cluster
  We consider the Cheeger constant $\phi(n)$ of the giant component of supercritical bond percolation on $\mathbb{Z}^d/n\mathbb{Z}^d$. We show that the variance of $\phi(n)$ is bounded by $\frac{\xi}{n^d}$, where $\xi$ is a positive constant that depends only on the dimension $d$ and the percolation parameter. 
Eviatar B. Procaccia, Ron Rosenthal
math.PR