## 4 Analytical Discussion
### Papers with Various Subfields
Attractive characteristics of YIG include a high Curie temperature, ultra-low damping (the lowest among all materials at room temperature), electrical insulation, strong chemical stability, and simple synthesis in the single crystalline form [18; 22; 81]. YIG's low magnetic damping makes it perfect for hybrid spintronic devices with graphene [22; 81]. Nowadays, ferromagnetic insulators (FMI) are extensively utilized. FMI enables the clear separation of spin-current and charges current effects. YIG is one of the prototype models of an FMI substance [16; 17; 18; 22]. By altering the ferrimagnetic insulator thickness and interface quality, the paper [17] reported the detection of a spin-Seebeck effect (SSE) characteristic: the SSE signal increases with the increase in YIG film thickness. * In fundamental device application research, a film with low damping is required. The nanometer-thick YIG film can generate minimal damping phenomena. For the deposition of submicron-thick films, pulsed laser deposition (PLD) and sputtering are the preferred methods [8]. Numerous top cited papers have described various YIG film preparation procedures to achieve high-quality film [25], including pulsed laser deposition (PLD) [13; 14; 15; 17; 75; 76; 77], laser molecular beam epitaxy (MBE) [18; 19], liquid phase epitaxy (LPE) [17; 20; 22; 24; 25; 84], sputtering [89; 92; 97; 103] and sol-gel methods [33; 34]. Gadolinium gallium garnet (Gd\({}_{3}\)Ga\({}_{5}\)O\({}_{12}\), GGG), silicon, yttrium aluminum garnet (YAG), and quartz are some of the substrates that have been utilized to deposit films. * Magnonics is a technology for low-power signal transmission and data processing based on the propagation of spin-waves (magnons) in magnetic materials [72; 78; 79; 106]. They have spin angular momentum and are bosonic [106]. Due to the rapid development of nanotechnology, magnonics is currently undergoing an explosion [72]. Yttrium iron garnet (YIG) is particularly intriguing for this application due to its lengthy magnon propagation length [78] and relatively low damping (\(\alpha\) < 10\({}^{4}\)) [106]. YIG also exhibits excellent magnetic and elastic properties [23]. In [72], the authors describe the inductive creation and detection of plane wave spin-waves in the low-power linear regime. In [106], both anisotropy and exchange-mediated magnon-phonon interactions are considered. Hence, YIG is used to study magnonic phenomena. YIG's centimeter-long magnon propagation length and graphene's excellent carrier mobility could lead to novel spintronic devices [22]. * The rise of this industry creates a demand for YIG films with nanometer-scale thickness and minimal damping, similar to YIG bulk materials and thick films. Nanofilms with such low damping properties are essential for both fundamental research, such as the study of spin pumping, and device applications, such as spin-torque oscillators [5; 8]. YIG functional layers for practical magnonics should be nanometer-thin with ultrasmooth surfaces to maximize data processing efficiency and to reduce the energy consumption of sophisticated spin-wave devices [25]. According to [PERSON] et al. [25], developing YIG films with thicknesses below 100 nm using LPE remains a challenge for conventional thick film LPE process. The prior top cited paper, [PERSON] et al. [5], successfully developed YIG film using sputtering with nanoscale (nm) thickness and achieved the lowest damping (\(\alpha\) = (8.58 \(\pm\) 0.21) \(\times\) 10\({}^{5}\) for spintronic development.