Nature and impact of stripe freezing in La$_{1.67}$Sr$_{0.33}$NiO$_4$

TL;DR

This paper investigates the charge and spin stripe orders in La$_{1.67}$Sr$_{0.33}$NiO$_4$, revealing a stripe freezing transition below 50 K characterized by neutron scattering and other probes.

Contribution

It provides a unified interpretation of charge and spin stripe behavior, identifying a stripe freezing and glassy spin order transition at low temperatures.

Findings

Charge and spin stripe orders develop around 200 K.

Evidence of stripe freezing and glassy spin order below 50 K.

Neutron scattering reveals a slight rotation of the average spin direction.

Abstract

La$_{1.67}$Sr$_{0.33}$NiO$_4$ develops charge and spin stripe orders at temperatures of roughly 200 K, with modulation wave vectors that are temperature independent. Various probes of spin and charge response have provided independent evidence for some sort of change below $\sim50$ K. In combination with a new set of neutron scattering measurements, we propose a unified interpretation of all of these observations in terms of a freezing of Ni-centered charges stripes, together with a glassy ordering of the spin stripes that shows up in neutron scattering as a slight rotation of the average spin direction.