Temperature dependence of the pseudogap in Y1−zPrzBa2Cu3O7−δ single crystals

Abstract

We investigate the conductivity in the basis plane of Y1−zPrzBa2Cu3O7−δ and YBa2Cu3O7−δ single crystals. The excess conductivity, Δσ, is described by Δσ ~ (1 − T/T*)exp(Δab*/T) in a wide temperature range Tf < T < T*, where T* is the mean field temperature of the superconducting transition. We determine that the temperature dependence of the pseudogap (PG) is described in terms of the BCS-BEC crossover theoretical model. It is observed that a reduction in the praseodymium content results to the widening of the temperature interval that the PG region is realized and a narrowing of the area of existence of the linear dependence of the resistivity, ρ(T), in the ab plane.