Pseudogap behavior of nuclear spin relaxation in high-T-c superconductors in terms of phase separation

We analyze anew experiments on the NMR in cuprates and find an important information on their phase separation and its strip character hidden in the dependence of 1/T-63(1) on the degree of doping. In a broad class of materials, 1/T-63(1) is the sum of two terms: the temperature-independent one attributed to incommensurate strips that occur at external doping and a universal temperature-dependent term ascribed to moving metallic and antiferromagnetic subphases. We argue that the frustrated first-order phase transition in a broad temperature interval bears a dynamical character. (C) 2004 MAIK Nauka/Interperiodica.