Density functional theory study of aluminium and chromium doped Yttrium ion garnet

Abstract

Density functional theory has been performed to investigate the atomic structure, electronic and magnetic properties of Al 3+ , Cr 3+ and Al 3+ –Cr 3+ co-doped cubic Y 3 Fe 5 O 12 (YIG) garnet crystal. Results show that Al 3+ and Cr 3+ ions are energetically substitution of Fe 3+ ions at the tetrahedral and octahedral sites in YIG, respectively. The doping concentration do not affect the preferential site occupancy for separate individual substitution. The magnetic moment increases and decreases for the single Cr and Al element doping, respectively. The magnetic moment and lattice constant decreases with the increase of Al–Cr concentrations. The magnetic moment decrease from 5.0 to 3.875 μ B linearly with x increases from 0 to 0.4 in Y 3 Al x Cr x Fe 5− x O 12 . These results indicate that doping can be adopted for the modification of magnetic properties of YIG.