Continuum of extended states in the spectrum of a one-dimensional random   potential
  We describe a one-dimensional disordered system, based on the Poschl-Teller potential, that exhibits a continuum of extended states which is independent of the random or correlated character of the sequence and of the length of the system. The delocalization of the electronic states occurs in the whole positive spectrum where the system shows a perfect transmission. 
Alberto Rodriguez and Jose M. Cervero