Complete phase diagram of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Sr</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>–</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:msub><mml:mi>La</mml:mi><mml:mi>x</mml:mi></mml:msub><mml:mi>Fe</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math> with versatile magnetic and charge ordering
Masaho Onose, H. Takahashi, Hajime Sagayama, Yuichi Yamasaki, Shintaro Ishiwata
Abstract
A detailed electronic phase diagram of perovskite-type oxides ${\mathrm{Sr}}_{1--x}{\mathrm{La}}_{x}\mathrm{Fe}{\mathrm{O}}_{3}$ ($0\ensuremath{\leqq}x\ensuremath{\leqq}0.5$) was established by synchrotron x-ray diffraction, magnetization, and transport measurements for polycrystalline samples synthesized by a high-pressure technique. Among three kinds of helimagnetic phases in $\mathrm{SrFe}{\mathrm{O}}_{3}$ at zero field, two of them showing multiple-$\mathbit{q}$ helimagnetic spin textures tend to rapidly disappear in cubic symmetry upon the La substitution with $x$ less than 0.1, which accompanies the loss of metallic nature. On the other hand, the third helimagnetic phase apparently remains robustly in ${\mathrm{Sr}}_{1--x}{\mathrm{La}}_{x}\mathrm{Fe}{\mathrm{O}}_{3}$ with $x$ higher than 0.1, followed by merging to the spin/charge ordered phase with $x\ensuremath{\sim}1/3$. We propose an important role of itinerant ligand holes on the emergence of multiple-$\mathbit{q}$ states and a possible link between the third (putative single-$\mathbit{q}$) helimagnetic phase in $\mathrm{SrFe}{\mathrm{O}}_{3}$ and the spin/charge ordered phase in ${\mathrm{Sr}}_{2/3}{\mathrm{La}}_{1/3}\mathrm{Fe}{\mathrm{O}}_{3}$.