Antiferromagnetic domain walls in lightly doped layered cuprates

TL;DR

This paper explains the temperature-dependent behavior of antiferromagnetic domain walls in lightly doped layered cuprates, linking ESR data to spin and charge ordering phenomena and structural twin boundaries.

Contribution

It presents a novel scenario connecting ESR observations with the evolution of AF domain walls and charge ordering in cuprates.

Findings

AF domain walls align with (110) twin boundaries at high temperatures.

Magnetic fields can annihilate domain walls, creating ferromagnetic and charged lines.

Low temperatures favor (100) orientation, rotating the AF easy axis by pi/4.

Abstract

Recent ESR data shows rotation of the antiferromagnetic (AF) easy axis in lightly doped layered cuprates upon lowering the temperature. We account for the ESR data and show that it has significant implications on spin and charge ordering according to the following scenario: In the high temperature phase AF domain walls coincide with (110) twin boundaries of an orthorhombic phase. A magnetic field leads to annihilation of neighboring domain walls resulting in antiphase boundaries. The latter are spin carriers, form ferromagnetic lines and may become charged in the doped system. However, hole ordering at low temperatures favors the (100) orientation, inducing a pi/4 rotation in the AF easy axis. The latter phase has twin boundaries and AF domain walls in (100) planes.