Untangling the contributions of cerium and iron to the magnetism of Ce-doped yttrium iron garnet

Abstract

The remarkable magnetic properties of yttrium iron garnets (YIGs) underpin the use of these materials in a broad scope of spintronic and photonic applications. In particular, the addition of rare earth metals in the structure enhances to a great extent the magneto-optical activity, which is beneficial for the development of nonreciprocal optical devices. Exploiting the wavelength selectivity of magneto-optics, we have identified a range of frequencies at which one can unravel the individual contributions to the magnetism and gyrotropic response arising from cerium and iron. We envision that this outcome may pave the way to further experiments to assess quantitatively the effect on the optical properties of rare earth incorporation into YIG.

Direct observation of multivalent states and 4f→3d charge transfer in Ce-doped yttrium iron garnet thin films

“…4(a)], the hysteresis curves of Ce-YIG films exhibit a small magnetization overshoot at the fields indicated above. These atypical magnetization curves are reminiscent of those that we obtained previously in our magneto-optical spectroscopy experiments [17].…”

“…The GGG substrates were chosen because of their best (i.e., lowest) lattice mismatch (0.057%) possible for growing YIG/Ce-YIG thin films [19,20]. Details of the thinfilm growth process and the magneto-optic characterization of the above Ce-doped YIG films [54-nm Ce-YIG(001) and 56-nm Ce-YIG(111)] and the 200-nm-thick YIG (111) film were already discussed in our recent work [17]. To study further the magnetic dynamic properties, we performed ferromagnetic resonance (FMR) experiments on the above Ce-YIG films.…”

“…It is unclear, however, whether both transitions are involved or if one of them prevails over the other. Recently, we found that the individual contributions to the magnetism by Ce and Fe ions could be resolved by magneto-optical spectroscopy for particular spectral regions in the visible range [17]. We suggested that this result may offer a future possibility to clarify the role of the aforementioned electronic transitions in the optical response of Ce-YIG since the dynamic magnetic responses of Ce and Fe might yield distinctive optical signatures in ultrafast optical experiments that could shed light on the relevance of intrasite Ce 3+ -Ce 3+ and intersite Ce 3+ -Fe 3+ transitions [17].…”

Sublattice spin reversal and field induced $Fe^{3+}$ spin-canting across the magnetic compensation temperature in $Y_{1.5}Gd_{1.5}Fe_{5}O_{12}$ rare-earth iron garnet

“…These two magnetic sublattices exhibit quite a different temperature dependance and as a result there exists a temperature at which the resultant Fe 3+ total magnetic moment is equal and opposite to the R 3+ magnetic moment resulting in zero total magnetization [6], known as magnetic compensation temperature (T Comp ). Therefore, a thorough understand- * varimalla@yahoo.com; vrreddy@csr.res.in ing of the macroscopic magnetic properties in RIG compounds is achieved from the knowledge of the different sublattices magnetization [21][22][23][24][25][26][27].…”

Giant magneto-optical Kerr enhancement from films on SiC due to the optical properties of the substrate

“…The magneto-optical Faraday and Kerr effects are powerful and sensitive probes of the electronic band structure of materials, revealing fundamental properties such as magnetic anisotropy [3,4], electron spin polarization, [5] and magnetic excitations [6]. Faraday and Kerr spectroscopy in the visible and infrared (IR) spectral ranges have been widely used to study metals [7], magnetic semiconductors [8][9][10][11], superconductors [12,13], and more recently graphene [14,15] and topological insulators [16]. These effects also play a vital role in modern technology, for example, Faraday isolators are commonly used to prevent unwanted feedback between devices in telecommunications.…”