Influence of Disorder on the Hall Effect in Bi$_2$Sr$_2$CuO$_{6+\delta}$

TL;DR

This study investigates how disorder affects the Hall effect in Bi$_2$Sr$_2$CuO$_{6+\delta}$, revealing weak doping dependence and proposing a scattering rate model to explain the Hall coefficient behavior.

Contribution

It provides new insights into the role of disorder and scattering mechanisms in the Hall effect of Bi-based cuprates, challenging previous theories about pseudogap states.

Findings

Hall coefficient deviation is weakly doping-dependent.

The Hall angle's temperature dependence is consistent across doping levels.

A phenomenological scattering rate model explains the Hall coefficient behavior.

Abstract

The in-plane resistivity and Hall coefficient have been measured for the single-layer compound Bi$_2$Sr$_2$CuO$_{6+\delta}$ for the whole range of doping states. The deviation of the Hall coefficient, $R_H$, from a high-temperature linear behavior and the temperature dependence of the Hall angle are both only weakly dependent upon doping, contrasting with Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$ and Bi$_2$Sr$_2$CaCuO$_{8+\delta}$. This is in contradiction with former proposals that the transverse transport detects the formation of incoherent Cooper pairs in the pseudogap state. Conversely, the analysis of the data using a phenomenological angular dependent scattering rate clearly allows to distinguish between underdoped and overdoped states, and we propose that the maximum in $R_H(T)$ simply arises due to the combination of a large isotropic scattering rate and an anisotropic temperature dependent one.