A systematic structural investigation of $\mathrm{F}{\mathrm{e}}_2\mathrm{M}{\mathrm{o}}_3{\mathrm{O}}_8$ as a function of pressure, temperature, and magnetic field reveals that the $P{6}_{3}mc$ space group remains robust over a wide range of conditions. No changes in the long-range crystal structure are observed for pressures up to 10 GPa, temperatures between 11 K and 300 K, and magnetic fields up to 9 T. The magnetostructural response, quantified by $\mathrm{\Delta }c/c$, is determined for magnetic fields applied transverse to the crystallographic $c$ axis, demonstrating strong magnetoelastic coupling. The well-known magnetic-field-induced transition is confirmed to be first order and isostructural, occurring between two distinct altermagnetic states. Importantly, this transition can also be accessed using magnetic fields applied within the $\mathit{ab}$ plane. When expressed in terms of the $c/a$ ratio, the structural evolution under pressure (0–10 GPa) maps continuously onto that observed across the full Zn substitution range in $(\mathrm{F}{\mathrm{e}}_{1-y}\mathrm{Z}{\mathrm{n}}_y{)}_2\mathrm{M}{\mathrm{o}}_3{\mathrm{O}}_8\left(0\le y\le 1\right)$, indicating a common underlying structural control parameter. These results demonstrate that the $c$-axis lattice parameter is the primary structural degree of freedom governing magnetic behavior under external tuning parameters. More broadly, they indicate that magnetic order in this family of complex oxides ($A_2\mathrm{M}{\mathrm{o}}_3{\mathrm{O}}_8, A=\mathrm{Co},\mathrm{Mn},\mathrm{Ni}$) can be systematically tuned via pressure. This tunability highlights these materials as promising platforms for controllable magnetic switching, particularly in thin films integrated with piezoelectric substrates.

Close

PrevNext

View figure in article

• Altermagnets
• Crystal structures
• Multiferroics
• X-ray diffraction