Multifractal spectra of mean first-passage time distributions in disordered chains

The multifractal characterization of the distribution over disorder of the mean first-passage time in a finite chain is revisited. Both, absorbing-absorbing and reflecting-absorbing boundaries are considered. Two models of dichotomic disorder are compared and our analysis clarifies the origin of the multifractality. The phenomenon is only present when the diffusion is anomalous.