Abstract
This paper is a brief review of the status of ‘phase separation’ ideas in manganites and cuprates,
mainly focused on the recent efforts by the authors. It is argued that in the last year considerable
progress has been made in the understanding of manganites, since the famous colossal
magnetoresistance peak in the resistivity versus temperature has been numerically observed in
unbiased Monte Carlo simulations using realistic models (namely, including double exchange,
phonons, and quenched disorder). It is also conjectured that a phenomenology similar to the one
found in manganites could be present in the underdoped regime of the cuprates. It is predicted
that a state with superconducting patches exists above the critical temperature in the
underdoped regime, in agreement with recent scanning tunneling microscopy experiments.
