Incommensurability of stripes in La_{2-x}Sr_xNiO_{4+y}

TL;DR

This paper derives an analytic formula for the incommensurability of static stripes in La_{2-x}Sr_xNiO_{4+y}, showing good agreement with experimental data and relating stripe stability to hole charge separation.

Contribution

It provides a new analytic expression for stripe incommensurability in nickelates, extending understanding from cuprates and linking stripe stability to charge separation.

Findings

Analytic formula matches neutron and X-ray data

Stripe incommensurability depends on hole density

Stripe stability linked to charge node separation

Abstract

An analytic expression for the incommensurability of static stripes in La_{2-x}Sr_xNiO_{4+y} is given, depending on the hole density n_h = x + 2y. Apart from geometry factors the formula is the same as for stripes in the related cuprates La_{2-x}Ae_xCuO_4 (Ae = Sr, Ba). Agreement with experimental data from neutron and X-ray diffraction is good. The stability of stripes is interpreted in terms of the separation of hole charges residing at every nu^{th} node of the associated magnetization waves.