Structural, Optical, and Magnetic Properties of Erbium-Substituted Yttrium Iron Garnets

Abstract

We synthesized a series of slightly erbium-substituted yttrium iron garnets (Er:YIG), Y 3– x Er x Fe 5 O 12 at different Er concentrations ( x = 0, 0.01, 0.05, 0.10, and 0.20) using a solid-state reaction and investigated their structural, magnetic, and optical properties as a function of Er concentration. The volume of the unit cell slightly increased with Er concentration and Er atoms predominately replaced Y atoms in the dodecahedrons of YIG. The optical properties exhibited certain decreases in reflectance in the 1500–1600 nm wavelength range due to the presence of Er 3+ . Despite the many unpaired 4f electrons in Er 3+ , the total magnetic moments of Er:YIG showed similar trends with temperatures and magnetic fields above 30 K. An X-ray magnetic circular dichroism study confirmed the robust Fe 3d magnetic moments. However, the magnetic moments suddenly decreased to below 30 K with Er substitution, and the residual magnetism ( M R ) and coercive field ( H C ) in the magnetic hysteresis loops decreased to below 30 K with Er substitution. This implies that Er substitution in YIG has a negligible effect on magnetic properties over a wide temperature range except below 30 K where the Er 4f spins are coupled antiparallel to the majority Fe 3d spins. Our studies demonstrated that above 30 K the magnetic properties of YIG are retained even with Er substitution, which is evidence that the Er doping scheme is applicable for YIG-based magneto-optical devices in the mid-infrared regime.

Self-Reconstructed Co-B Active Sites for High-Efficiency Hydrolysis of Ammonia Borane

“…The strongest peak in the spectrum of Co 9 Er 1 O x exists at a k value of ∼6.12 Å –1 , and an R value of ∼1.40 Å indicates the existence of Co-O coordination similar to that of Co 2 O 3 , while the disappearance of peaks at higher k and R values for the Co-Co configuration confirms the ultrasmall size of Co species. Figure d,e shows the XANES and EXAFS curves of Co 9 Er 1 O x at the Er L 3 -edge, in which the curve shapes are all very similar to that of Er 2 O 3 reported in the literature, − suggesting the presence of the Er 2 O 3 composition in Co 9 Er 1 O x . Based on the above results, it can be concluded that the Co 9 Er 1 O x catalyst is mainly CoO x (with Co 3+ ) tiny particles dispersed on the Er 2 O 3 substrate, with a strong particle-substrate interaction to facilitate the reaction.…”

Rare Earth Based Iron Garnet – A Survey on Its Magnetic Properties

“…When YIG is doped with erbium (Er), the magnetic moment is not influenced much over a wide temperature range except below 30K where the unpaired 4f electrons are coupled antiparallelly with the 3d electrons of iron cations [34]. Thus Er:YIG exhibits antiferromagnet-like behaviour at this lower temperature whereas above this and at room temperature it exhibits ferromagnetic behaviour.…”

Effect of Gadolinium Addition on Magnetic and Magneto-Optical Properties of Yttrium Iron Garnet Crystal

“…Among them, the dodecahedral c-site can accommodate rare earth ions with a large radius, while the tetrahedral a-site and octahedral d-site are typically used for doping ions with a smaller radius. 10,11 So far, there have been many reports on the modification of yttrium iron garnets by ions doping, especially Ce 3+ and Bi 3+ ions have been confirmed to have a significant effect on the improvement of magnetooptical properties. 12−15 16 Aung et al reported Bi 3+ ion-doped Bi x Y 3−x Fe 5 O 12 (x = 0−1.1) ceramics, which possess a FRA of −970°/cm at 1550 nm.…”

“…It can be seen that the structure possesses three sites: a-site, c-site, and d-site. Among them, the dodecahedral c-site can accommodate rare earth ions with a large radius, while the tetrahedral a-site and octahedral d-site are typically used for doping ions with a smaller radius. , So far, there have been many reports on the modification of yttrium iron garnets by ions doping, especially Ce 3+ and Bi 3+ ions have been confirmed to have a significant effect on the improvement of magneto-optical properties. − Ikesue et al reported that Ce 0.24 Y 2.76 Fe 5 O 12 ceramic was prepared by hot isostatic press and atmosphere sintering technology, and the FRA of Ce 0.24 Y 2.76 Fe 5 O 12 ceramic at 1550 nm band can reach 990°/cm . Aung et al reported Bi 3+ ion-doped Bi x Y 3– x Fe 5 O 12 ( x = 0–1.1) ceramics, which possess a FRA of −970°/cm at 1550 nm .…”