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تسجيل مستخدم جديدSurvey of temperature dependence of the damping parameter in the ferrimagnet Gd$_3$Fe$_5$O$_{12}$
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The damping parameter ${alpha}_{text{FM}}$ in ferrimagnets defined by following the conventional practice for ferromagnets is known to be strongly temperature dependent and diverge at the angular momentum compensation temperature, where the net angular momentum vanishes. However, recent theoretical and experimental developments suggest that the damping parameter can be defined in such a way, which we denote by ${alpha}_{text{FiM}}$, that it is free of the diverging anomaly at the angular momentum compensation point and is little dependent of temperature. To further understand the temperature dependence of the damping parameter in ferrimagnets, we analyze several data sets from literature for gadolinium iron garnet (Gd$_3$Fe$_5$O$_{12}$) by using the two different definitions of the damping parameter. Using two methods to estimate the individual sublattice magnetizations, which yield results consistent with each other, we found that in all the used data sets, the damping parameter ${alpha}_{text{FiM}}$ does not increase at the angular compensation temperature and shows no anomaly whereas the conventionally defined ${alpha}_{text{FM}}$ is strongly dependent on the temperature.
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Ferrimagnetic Y$_3$Fe$_5$O$_{12}$ (YIG) is the prototypical material for studying magnonic properties due to its exceptionally low damping. By substituting the yttrium with other rare earth elements that have a net magnetic moment, we can introduce a
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We demonstrate the magnetically-induced transparency (MIT) effect in Y$_3$Fe$_5$O$_{12}$(YIG)/Permalloy(Py) coupled bilayers. The measurement is achieved via a heterodyne detection of the coupled magnetization dynamics using a single wavelength that
probes the magneto-optical Kerr and Faraday effects of Py and YIG, respectively. Clear features of the MIT effect are evident from the deeply modulated ferromagnetic resonance of Py due to the perpendicular-standing-spin-wave of YIG. We develop a phenomenological model that nicely reproduces the experimental results including the induced amplitude and phase evolution caused by the magnon-magnon coupling. Our work offers a new route towards studying phase-resolved spin dynamics and hybrid magnonic systems.
Long-distance transport of spin information in insulators without long-range magnetic order has been recently reported. Here, we perform a complete characterization of amorphous Y$_3$Fe$_5$O$_{12}$ (a-YIG) films grown on top of SiO$_2$. We confirm a
clear amorphous structure and paramagnetic behavior of our a-YIG films, with semiconducting behavior resistivity that strongly decays with increasing temperature. The non-local transport measurements show a signal which is not compatible with spin transport and can be attributed to the drop of the a-YIG resistivity caused by Joule heating. Our results emphasize that exploring spin transport in amorphous materials requires careful procedures in order to exclude the charge contribution from the spin transport signals.
Magnetic moments in an ultra-thin Pt film on a ferrimagnetic insulator Y$_3$Fe$_5$O$_{12}$ (YIG) have been investigated at high magnetic fields and low temperatures by means of X-ray magnetic circular dichroism (XMCD). We observed an XMCD signal due
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