Hole concentration dependence of the ordering process of the stripe order in La2-xSrxNiO4

Abstract

Ordering process of stripe order in ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{NiO}}_{4}$ with x being around 1/3 was investigated by neutron-diffraction experiments. When the stripe order is formed at high temperature, incommensurability $\ensuremath{\epsilon}$ of the stripe order has a tendency to show the value close to 1/3 for the samples with x at both sides of 1/3. With decreasing temperature, however, $\ensuremath{\epsilon}$ becomes close to the value determined by the linear relation of $\ensuremath{\epsilon}{=n}_{h},$ where ${n}_{h}$ is a hole concentration. This variation of the $\ensuremath{\epsilon}$ strongly affects the character of the stripe order through the change of the carrier densities in stripes and antiferromagnetic domains.