The magnetic properties of EuAlSi, a compound comprising a honeycomb lattice of Al/Si atoms and a triangular lattice of Eu atoms, are presented. By means of single-crystal x-ray diffraction, we find that EuAlSi crystallizes in an ${\mathrm{AlB}}_2$-type structure with space group $P6$/mmm and unit cell parameters $a=4.2229\left(10\right)\AA$ and $c=4.5268\left(12\right)\AA$. Our magnetic measurements indicate that EuAlSi is a soft ferromagnetic material with $T_{\mathrm{Curie}}=25.8\mathrm{K}$. The susceptibility follows the Curie-Weiss law at high temperatures, which allowed us to determine the paramagnetic Curie temperature ${\theta }_P=36.2\left(1\right)\mathrm{K}$ and an effective magnetic moment ${\mu }_{\text{eff}}=8.07\left(1\right){\mu }_B/\mathrm{Eu}$. This value is in agreement with the theoretical value of $7.9{\mu }_B$ for ${\mathrm{Eu}}^{2+}$ free ion. Moreover, we have prepared the ${\mathrm{Eu}}_{1-x}{\mathrm{Sr}}_x\mathrm{AlSi}$ solid solution, where the atoms in the triangular lattice were systematically exchanged, in order to study the evolution of the collective quantum properties from the ferromagnetic EuAlSi toward the superconducting SrAlSi. Across the ${\mathrm{Eu}}_{1-x}{\mathrm{Sr}}_x\mathrm{AlSi}$ solid solution, the unit cell parameters change linearly, following Vegard’s law, and making the system reliable for studying composition dependence of the interplay between the crystal structure and physical properties. As the Sr content increases, i.e., $x$ increases, we note a consistent reduction of ${\mu }_{\mathrm{eff}}$ and $T_{\mathrm{Curie}}$. Long-range magnetic order in ${\mathrm{Eu}}_{1-x}{\mathrm{Sr}}_x\mathrm{AlSi}$ persists up to $x=0.95$, whereas superconductivity is only observed for samples with $x>0.97$.

Close

PrevNext

Reuse & PermissionsView figure in article

• 
• 
• 
• 
• 
• 
• 

• Magnetic order
• Magnetic susceptibility
• Magnetism
• Superconductivity