Unified model of the Hall effect from insulator to overdoped compounds in cuprate superconductors

Abstract

Measurements of the Hall coefficients in La2−xSrxCuO4, ranging from the undoped (x=p=0) Mott insulator to overdoped compounds, exhibit a temperature dependence that offers insights into these compounds' electronic structure. We interpret these results using a model based on the theory of phase-separation dynamics, which begins at half-filled (n=1) and at a temperature TPS(p), near the pseudogap temperature T*(p). The n=1 holes have low mobility and provide the modulations of the charge density waves (CDW). As doping increases from p=0, these modulations guide the additional p holes to occupy alternating CDW domains. This charge inhomogeneity may facilitate the formation of localized superconducting amplitudes below the critical onset temperature Tcmax(p). Using thermal activation expressions, along with quantum tunneling between the charge domains, we successfully reproduce all Hall coefficient measurements RH(p,T) and highlight the relevant energies of the cuprates. The calculations confirm three significant electronic features: the phase-separating role of the pseudogap temperature, the superconducting state achieved through phase coherence, and the two types of charge carriers whose energies and mobilities become comparable at p≈0.19, where T*(p)≈Tcmax(p). This results in a crossover from n=p to n=1+p. These findings, along with the RH(p,T) calculations from insulating to overdoped compounds, underscore the critical role of the electronic phase separation in the properties of cuprates.

Source-reported materials — not catalogue approval

Similar papers