Nature of the magnetic stripes in fully oxygenated La$_{2}$CuO$_{4+y}$

TL;DR

This study uses neutron scattering to investigate magnetic stripe behavior in optimally oxygen-doped La$_{2}$CuO$_{4+y}$, revealing coexisting static and dynamic magnetic orders alongside superconductivity.

Contribution

It provides detailed insights into the coexistence and characteristics of static and fluctuating magnetic stripes in La$_{2}$CuO$_{4+y}$, a high-temperature superconductor.

Findings

Magnetic stripes are equally oriented along both tetragonal axes.

Fluctuating stripes have significant in-plane and out-of-plane spin components.

Static magnetic order and low-energy fluctuations coexist with superconductivity.

Abstract

We present triple-axis neutron scattering studies of static and dynamic magnetic stripes in an optimally oxygen-doped cuprate superconductor, La$_{2}$CuO$_{4+y}$, which exhibits a clean superconducting transition at $T_{\rm c}=42$ K. Polarization analysis reveals that the magnetic stripe structure is equally represented along both of the tetragonal crystal axes and that the fluctuating stripes display significant weight for in-plane as well as out-of-plane spin components. Both static magnetic order as well as low-energy fluctuations are fully developed in zero applied magnetic field and the low-energy spin fluctuations at $\hbar \omega = 0.3-10$ meV intensify upon cooling. We interpret this as an indication that superconductivity and low-energy spin fluctuations co-exist microscopically in spatial regions which are separated from domains with static magnetic order.