Non-linear Hall effect in PCCO electron-doped cuprate

The Hall effect in electron-doped cuprates shows non-trivial behaviors as a function of doping and temperature. For example, the Hall coefficient of Pr_2-xCe_xCuO₄ at x = 0.17 shows two sign changes between 0 and 300K. This can be explained in part using a two-carrier model. We present a quantitative analysis of the non-linear Hall effect for PCCO thin films as a function of doping. We measure the longitudinal and Hall resistivity of high quality PCCO thin films deposited by Pulsed Laser Deposition patterned using photolithography techniques. We focus on the non-linear magnetic field dependence of the Hall resistivity easily evidenced at temperatures where R_H ~ 0. Considering higher orders of field in the equation . we observe in fact that the Hall coefficient shows this non-linear behavior at all temperatures and that it evolves also with doping. An analysis of this non-linear field dependence within a simple two-band model is presented. Results show that one needs to go beyond this simplistic model to improve our understanding of the band structure of these materials and the impact of the Fermi surface transformation as a function of doping.