Within conventional theory, for a single band metal, the Hall number in the low temperature, high Field limit n_H(0) is equal to the carrier density. The evolution of n_H(0) with hole doping p in YBa₂Cu₃O_6+x shows an apparent rapid transition from n_H(0)=p to n_H(0)=1+p which has been interpreted as evidencing a reconstruction of the Fermi surface which coincides with the material entering the pseudogap regime. Here I present results for the overdoped cuprate Tl₂Ba₂CuO_6+x (Tl2201) which also shows such a transition but is, in this case , more gradual with n_H(0) becoming equal to 1+p only at the edge of the superconducting dome. Furthermore, in Tl2201 this transition does not appear to accompany entry into a pseudogap regime. The evolution of n_H correlates with the emergence of the anomalous linear-in-T term in the low-T in-plane resistivity. The results could suggest that quasiparticle decoherence extends to dopings well beyond the pseudogap regime.

Keywords: Normal state properties, pseudogap, Tl2Ba2CuO6+x