Hall coefficient in the ground state of stripe-ordered La_2-x_Ba_x_CuO_4_ single crystals

TL;DR

This study investigates how the Hall coefficient varies with temperature and hole concentration in stripe-ordered La_2-x_Ba_x_CuO_4_ superconductors, revealing sign changes and zero values linked to stripe order stability.

Contribution

It provides new insights into the relationship between stripe order and electronic transport properties in high-T_c cuprates, highlighting the dependence of the Hall coefficient on hole doping levels.

Findings

R_H_ is zero at x=1/8 in the ground state of stripe order.

R_H_ becomes negative for x<1/8, indicating a change in charge carrier behavior.

Hall coefficient behavior is linked to the balance of hole-like and electron-like contributions.

Abstract

Temperature dependence of the Hall coefficient, R_H_, has been investigated in charge-spin stripe-ordered La-214 high-T_c_ superconductors. Using the simplest stripe-ordered system of La_2-x_Ba_x_CuO_4_, it has been clarified that both the behavior of R_H_ and its sign exhibit significant dependences on the hole concentration. That is, R_H_ is zero in the ground state of the charge-spin stripe order at x=1/8, while it is negative in the less-stabilized state of the charge stripe for x<1/8. These are interpreted as owing to the delicate balance of the contributions of the hole-like Fermi surface and the possible electron pocket arising from the formation of the charge-spin stripe order.