High Anisotropy Field Research Articles

Development of high superconductor fraction (Ba, K)Fe2As2 wires with improved uniformity by two-axial rolling

Iron-based superconductors are regarded as prospective candidates for high magnetic field applications since they have very high upper critical field and low anisotropy. For practical applications, it is important to develop superconducting wires with strong current carrying capability. In this work, Cu/Ag composite sheathed (Ba, K)Fe2As2 (Ba-122) iron-based superconducting wires were fabricated by a two-axial rolling deformation process and a subsequent hot isostatic pressing (HIP) heat treatment. Compared with the previously reported Cu/Ag/Ba-122 wires prepared by groove rolling, the two-axial rolling allowed to use much thinner Cu/Ag composite sheath for wire fabrication, thus greatly increasing the filling factor of superconducting materials by about 5 times to 24 %, and lowering the volume fraction of silver down to 16 % in wires. By a comparative study on the microstructure and superconducting properties between the wires made by two-axial rolling and groove rolling processes, it is found that besides the significantly increased engineering critical current density, the former also exhibits improved homogeneity of mass distribution and uniformity of Ba-122/Ag interfaces, resulting in significantly enhanced n-values over 40 in magnetic fields up to 14 T. Our work suggests that two-axial rolling, combined with HIP processes, presents a promising approach to prepare iron-based superconducting wires with high filling factor, high uniformity and low cost for practical applications.

Effect of annealing temperature on crystallographic texture, magnetic and microwave properties of barium ferrite thin films

Due to it has large saturation magnetization (Ms), high magnetocrystalline anisotropy field and high ferromagnetic resonance (FMR) frequency, barium ferrite (BaM) has attracted more and more attentions in the fields of magnetic recording media, permanent magnets and microwave devices. Here, BaM thin films were deposited on Pt/TiO2/SiO2/Si substrates, and the effect of annealing temperature on the microstructure, magnetic and microwave properties of barium ferrite thin films was investigated in detail. It is found that when the BaM thin film was annealed at 1035 °C, it has good properties. The XRD data provide clear evidence that the BaM thin films have high c-axis orientation, and the Lotgering factor is as high as 0.96. The AFM morphology show that BaM grains are out of the film plane, and they are hexagonal. The magnetic hysteresis curves indicated that both saturated magnetization (4πMs), remanence ratio and coercive (Hc) for out of plane increase with increasing Ta first, then decreased, and get the maximum value at 1035 °C. The ferromagnetic resonance (FMR) measurement show that the FMR linewidth is 143 Oe@50 GHz, it means that this this sample has low microwave loss in millimeter wave loss, and the FMR absorption can be tuned by applied magnetic field. These results make sure that this BaM thin film is possible use in millimeter wave devices such as filers, circulators and isolators.

Microstructure, microchemistry, and micro-magnetism of Dy grain boundary diffused (Nd, Ce)–Fe–B magnets

The microstructure of (Nd, Ce)–Fe–B sintered magnets with different diffusion depths was characterized by a magnetic force microscope, and the relationship between the magnetic properties and the local structure of grain boundary diffused magnets is discussed. The domains perpendicular to the c-axis (easy magnetization direction) show a typical maze-like pattern, while those parallel to the c-axis show the characteristics of plate domains. The significant gradient change is shown in the concentration of Dy with the direction of diffusion from the surface to the interior. Dy diffuses along grain boundaries and (Dy, Nd)2Fe14B layer with a high anisotropy field formed around the grains. Through in-situ electron probe micro-analysis/magnetic force microscopy (EPMA/MFM), it is found that the average domain width decreases, and the proportion of single domain grains increases as diffusion depth increases. This is caused by both the change of concentration and distribution of Dy. The grain boundary diffusion process changes the microstructure and microchemistry inside the magnet, and these local magnetism differences can be reflected by the configuration of the magnetic domain structure.

Perpendicular magnetic anisotropy and magneto-optical properties of Bi,Mn:YIG epitaxial films

Bi,Mn co-doped Y3Fe5O12 films with good crystallinity, great magneto-optical properties and high perpendicular magnetic anisotropy field (>3000 Oe) were prepared via liquid phase epitaxy.

The effect of Nd content on the elemental interdiffusion mechanism of Nd–Dy–Fe–B magnets

In this work, the effect of Nd content on the interdiffusion mechanism of Nd/Dy elements in Nd-Dy-Fe-B magnets was elucidated by studying the differences in the magnetic properties, microstructure, and demagnetization process. As the Nd content increased, a uniform, continuous, and thicker layer of rare earth-rich (RE-rich) phase formed inside the magnets, which had a good magnetic isolation effect. During the demagnetization process, the strong ferromagnetic coupling effect between the main phase grains could be effectively weakened. At the same time, the thicker RE-rich phase layer could lead to a more obvious interdiffusion phenomenon of Nd/Dy elements, forming more (Nd, Dy)2Fe14B phases with high magnetocrystalline anisotropy fields, resulting in higher coercivity of the magnets. This paper elucidated the influence of Nd content on the interdiffusion mechanism of dual alloy Nd-Dy-Fe-B magnets, which had important significance for the preparation of high-performance Nd-Dy-Fe-B magnets.

A Novel Spinel Ferrite-Hexagonal Ferrite Composite for Enhanced Magneto-Electric Coupling in a Bilayer with PZT.

The magnetoelectric effect (ME) is an important strain mediated-phenomenon in a ferromagnetic-piezoelectric composite for a variety of sensors and signal processing devices. A bias magnetic field, in general, is essential to realize a strong ME coupling in most composites. Magnetic phases with (i) high magnetostriction for strong piezomagnetic coupling and (ii) large anisotropy field that acts as a built-in bias field are preferred so that miniature, ME composite-based devices can operate without the need for an external magnetic field. We are able to realize such a magnetic phase with a composite of (i) barium hexaferrite (BaM) with high magnetocrystalline anisotropy field and (ii) nickel ferrite (NFO) with high magnetostriction. The BNx composites, with (100 - x) wt.% of BaM and x wt.% NFO, for x = 0-100, were prepared. X-ray diffraction analysis shows that the composites did not contain any impurity phases. Scanning electron microscopy images revealed that, with an increase in NFO content, hexagonal BaM grains become prominent, leading to a large anisotropy field. The room temperature saturation magnetization showed a general increase with increasing BaM content in the composites. NFO rich composites with x ≥ 60 were found to have a large magnetostriction value of around -23 ppm, comparable to pure NFO. The anisotropy field HA of the composites, determined from magnetization and ferromagnetic resonance (FMR) measurements, increased with increasing NFO content and reached a maximum of 7.77 kOe for x = 75. The BNx composite was cut into rectangular platelets and bonded with PZT to form the bilayers. ME voltage coefficient (MEVC) measurements at low frequencies and at mechanical resonance showed strong coupling at zero bias for samples with x ≥ 33. This large in-plane HA acted as a built-in field for strong ME effects under zero external bias in the bilayers. The highest zero-bias MEVC of ~22 mV/cm Oe was obtained for BN75-PZT bilayers wherein BN75 also has the highest HA. The Bilayer of BN95-PZT showed a maximum MEVC ~992 mV/cm Oe at electromechanical resonance at 59 kHz. The use of hexaferrite-spinel ferrite composite to achieve strong zero-bias ME coupling in bilayers with PZT is significant for applications related to energy harvesting, sensors, and high frequency devices.

Strategy and mechanism for substantially enhanced coercivity in multi-main-phase Nd-La-Ce-Fe-B sintered magnets

Improving the coercivity of high La/Ce content multi-main-phase (MMP) sintered magnets is crucial for promoting the use of La/Ce elements in permanent magnets. In this work, we used a novel strategy to accurately manipulate the chemical heterogeneity and grain boundary (GB) structures of MMP Nd-La-Ce-Fe-B sintered magnets, namely, by adjusting the composition of the LaCe-free alloys. We obtained an ultrahigh coercivity value of 13.75 kOe for the MMP-LaCe35 (LaCe accounted for 35 wt.% of total rare earth) magnet. This was attributed to the effect of Al-Cu-Ga element addition in LaCe-free alloys toward enhancing chemical heterogeneity (thicker Nd-rich shells) and optimizing the GB structures (continuous lamellar GBs). The former had a higher anisotropy field (HA) value, which enhanced the nucleation field, while the latter had a lower Fe concentration, which improved the magnetic isolation effect. Based on the above mechanisms, a coercivity of 12.09 kOe was attained for the MMP-LaCe40 magnet produced utilizing an alloy with the same composition. In addition, reducing the Nd content while maintaining the addition of Al-Cu-Ga elements in the LaCe-free alloy proved that adding Al-Cu-Ga elements improved the GB phase wettability of the MMP magnets, thereby forming continuous lamellar GBs to enhance coercivity. Our findings revealed that the enhanced chemical heterogeneity also effectively improved the coercivity temperature stability of the MMP magnets. This study provided an effective and feasible strategy for microstructure manipulation to prepare ultrahigh coercivity MMP-sintered magnets with higher LaCe content, which is crucial for promoting the comprehensive utilization of rare earth resources.

Study on the Microstructure and Magnetic Properties of Nd-Fe-B/Fe-Co Composite Nanowires.

To solve the problem of the low coercivity of Nd-Fe-B-based nanowires impeding their application in magnetic storage media, highly ordered Nd-Fe-B/Fe-Co composite nanowires were fabricated in an anodic alumina template by means of the alternating electrochemical deposition method. In this paper, the effect of soft and hard magnetic phase compositing on the magnetic properties of Nd-Fe-B-based nanowires was investigated, and the coercivity improvement mechanism was demonstrated. The results show that after annealing at 600 °C for 2 h, Nd-Fe-B/Fe-Co nanowires crystallize into a multiphase structure containing a hard Nd2(Fe, Co)14B phase and soft NdB4, NdB6, Fe7Nd, and Fe7Co3 phases. It is characterized that the Nd2(Fe, Co)14B phase preferentially nucleates, followed by NdB4 + NdB6 + Fe7Nd, while Fe7Co3 has been formed in as-deposited nanowires. The existence of a Nd2(Fe, Co)14B phase with high anisotropy fields, the remanence enhancement effect produced by exchange coupling between hard-soft magnetic phases, and the pinning effect between different phases make the composite nanowires approximately exhibit single hard magnetic phase characteristics with coercivity and remanence ratio as high as 4203.25 Oe and 0.89. The results indicate that synthesizing Nd-Fe-B/Fe-Co exchange-coupled composite nanowires via alternating electrodeposition is an effective way to optimize the magnetic performance of Nd-Fe-B-based nanowires.

Pr–Tb synergistic strengthening on coercivity of Nd-Ce-Fe-B magnets grain boundary diffused with Pr-Tb-Al-Ga alloys

Sintered Nd-Ce-Fe-B magnets were grain boundary diffused (GBDed) with PrxTb80–xAl10Ga10 (at%) (x = 0, 20, 40, 60, 80) alloys. The effect of Pr/Tb content in diffusion source on magnetic properties, microstructure and elements distribution of GBDed magnets was investigated. When Pr is used to substitute for 75% Tb in diffusion source, Tb consumption per unit coercivity improvement of GBDed magnet reduces by 77%, compared with the Tb80Al10Ga10 diffused magnet. Tb element diffuses into magnets and then forms Tb-rich shell with high magneto-crystalline anisotropy field surrounding main phase grains, resulting in substantial coercivity improvement. Pr with low melting point diffuses deeply along liquid grain boundary phase during GBD process. It can eliminate some sharp defects of main phase grains and make grain boundaries smooth, which provides diffusion channels for further diffusion of Tb element. Therefore, there are more diffusion channels for Tb and less Tb enriched at surface region, making Tb diffuse more deeply and improving Tb utilization efficiency. This method significantly improves the coercivity, and realizes the green, efficient and high-quality utilization of heavy rare earth (HRE) elements.

Impact of vanadium substitution on structural, magnetic, microwave absorption features and hyperfine interactions of SrCo hexaferrites

The Co-V co-substituted nano Sr-hexaferrite, Sr0.5Co0.5VxFe12−xO19 (0.00 ≤ x ≤ 0.08) (V→SrCo (0.00 ≤ x ≤ 0.08) NHFs), were manufactured by citrate combustion route. The microstructure, morphology, magnetic features, hyperfine interactions and oxidation state and chemical composition of products explained by XRD, SEM with EDX, HR-TEM, VSM, Mossbauer spectrometry, and XPS, respectively. The DXRD (Average crystallite size) of products were assessed via Scherrer formula as within the range of 37 and 83 nm. The hexagonal morphology and chemical composition of the products was presented by TEM, HR-TEM, SEM and EDX analyses. The XPS analysis provided both the composition and oxidation states of prepared NHFs. Mossbauer spectra showed that the s electron density around Fe3+ ions of all sites except 12k influenced V3+ content. The coercivity data indicates that all samples denote a magnetically hard material at both low and high temperatures. Ms, Mr and nB fluctuate with respect to dopant concentration and attain their highest magnitudes for the V→SrCo (x = 0.04) NHFs. A SQR of around 0.5 is achieved at each temperature, reflecting a relatively high large anisotropy field. The field-cooling (FC) curves of all samples yield a drop in magnetization with increasing temperature. Their irreversibility temperature is detected to be beyond 325 K. Both M-H and M-T imply the ferrimagnetic behavior of different samples. Microwave properties were measured between 2 and 18 GHz as S11-S21 parameters. It demonstrated non-linear behavior of the microwave properties vs. V concentration. The origin of the reflection losses in NHVs can be explained by the dipole polarization processes.

Microstructure evolution of Pr-doped SmCo4B-based ribbons with improved magnetization

Searching for high-performance permanent magnets is always challenging for modern technological applications. The novel SmCo4B phase has a higher anisotropy field than SmCo5, and this paper disclosed the effect of Pr addition on the phase transformation, microstructure evolution, and magnetism of the multi-element doped Sm1−xPrxCo3.04Fe0.9Cu0.06B ribbons. The results show that Pr addition decreases the amorphous forming ability of the as-spun ribbons. After annealing, Pr addition promotes the growth of strip-like Sm-Co-B grains, and 8 at% Pr addition increases the saturation magnetization and remanence of the Sm-Co-B ribbons by 96.2% and 48.0%, respectively. Pr addition weakens the anisotropy field of the Sm-Co-B phase, resulting in a gradual decrease in coercivity. We revealed the transformation mechanism of strip-like grains during melt-spinning and annealing, found the relationship between phase content, dislocation density, strain, and grain size, and proposed the corresponding microstructure evolution models.

Microstructure and magnetic properties of grain boundary diffused Nd-Fe-B magnets with Tb-Al-Ga alloy

The coercivity of Nd-Fe-B magnets can be effectively improved by grain boundary diffusion using low melting point alloy as diffusion source. In this work, Tb-Al-Ga alloy was used as diffusion source for grain boundary diffused Nd-Fe-B magnets. Tb-rich shell structure, potential synergistic effect of Al-Ga, interface between diffusion source and the magnets were analyzed. When the magnets were processed at 875 °C for 10 h, the coercivity increased by 123 % from 10.38 kOe to 23.15 kOe and the remanence and the maximum magnetic energy product only decreased by 3 %. Tb element mainly formed shell structure with high magneto-crystalline anisotropy field surround the main phase grains. Non-magnetic Al element was distributing around the main phase grains as network structure, which could well isolate the main phase grains. The Tb-rich shell with high magneto-crystalline anisotropy field and the non-magnetic phase with magnetic exchange decoupling between the adjacent grains contributed to substantial increase in the coercivity of the grain boundary diffused magnets. The grain boundary phase was wetted by Al element, which promoted Tb element diffused into the magnets more deeply.

C-axis Oriented Polycrystalline BaFe12-xCoxO19 (x = 0, 0.3, 0.6, 0.9) for Millimeter Wave Self-biased Circulator at Ka Band

The anisotropic hexagonal magnetic material is prepared using conventional ceramic process. The high magnetic anisotropy field of hexagonal is essential to extend the device bandwidth for circulator operating at millimeter wave band. The modified hexagonal BaFe12-xCoxO19 with about 9 kOe anisotropy field and its Electromagnetic property are presented. And a simulation certificating the circulator at Ka-band is given at the end of the paper.

Microstructure regulation and optimizing magnetic properties of (La, Ce, Pr)17Fe78B6 alloy via short-range grain boundary diffusion

Increasing the utilization ratio of La and Ce in rare earth permanent magnets is an effective measure to solve the balance utilization of rare earth resources. In this work, nanocrystalline melt spun [(Ce0.7La0.3)0.3Pr0.7]17Fe78B6 powder and low melting point PrTbCu alloy were used as the initial material and the diffusion source for short-range grain boundary diffusion (SRGBD) to improve the coercivity. High coercivity of up to 18.21 kOe can be achieved, enhancing by 108.82% compared with the initial powder, and meanwhile, the remanence was only slightly reduced by 2.13%. After that, nanocrystalline bulk magnets with excellent magnetic performance were produced through spark plasma sintering (SPS). TEM observation reveals that the bcc-RE2O3 intergranular phase that induced by short-range grain boundary diffusion is distributed between adjacent matrix phase grains, which is conductive to the improvement of magnetic isolation effect. EDS results show that the Tb-rich shell with high magnetocrystalline anisotropy field has formed. Moreover, it is found that Tb diffuses into the 2:14:1 phase more easily than Pr element during the initial stage of diffusion. Enhanced magnetic isolation effect and the formed Tb-rich shell in grain surface contributed to high coercivity.

Sub-terahertz/terahertz electron resonances in hard ferrimagnets

Intensive development of ultrafast electronics requires materials with high-frequency spin dynamics. In this light, the insulators that possess the magnetization precession phenomenon due to magnetic anisotropy are dark horses. On the one hand, modern hard magnetic materials reveal relatively moderate resonance frequencies of the ferromagnetic mode (generally, dozens of GHz), which are lower than the frequencies of the antiferromagnetic resonances; on the other hand, the research in this area is quite scanty, which implies a room for a breakthrough. Here, an example of a hard ferrimagnetic insulator (cobalt ferrite CoFe2O4) was obtained in the form of nanoparticles and bulk ceramics via high-temperature methods. Due to high magnetic anisotropy fields, the samples in a single domain state show broad hysteresis loops. The materials also possess intensive resonance absorption at frequencies higher than 0.20 THz in zero external magnetic fields. For the first time, natural ferromagnetic resonance (NFMR) frequencies higher than 0.30 THz were registered. The ceramic sample demonstrates the highest-known NFMR frequency of 0.35 THz. The model based on the Landau-Lifshitz equation was developed to explain the demonstrated magnetodynamic properties and shed light on those of hard ferrimagnets in general. The practical application of the electron resonances in hard magnetic insulators, including cobalt ferrite, Al-doped M-type hexaferrite, and epsilon iron oxide, is discussed. Our findings reveal that these materials should provide several orders of magnitude more powerful spin pumping at sub-terahertz/terahertz frequencies compared to insulating antiferromagnets, even under unpolarized irradiation and even in the absence of external magnetic fields. This opens new horizons for the development of practical ultrafast electronics.

Magnetic Properties and Microstructure of FePt(BN, X, C) (X = Ag, Re) Films.

A sputtered FePt(BN, Re, C) film, here boron nitride (BN), was compared to a reference sample FePt(BN, Ag, C). Intrinsically, these films illustrate a high anisotropy field (Hk) and perpendicular magnetocrystalline anisotropy (Ku),although the reference sample shows a higher value (Hk = 69.5 kOe, Ku = 1.74 × 107 erg/cm3) than the FePt(BN, Re, C) film (Hk = 66.9 kOe, Ku = 1.46 × 107 erg/cm3). However, the small difference in the anisotropy constant (K2/K1) ratio presents a close tendency in the angular dependence of the switching field. Extrinsically, the out-of-plane coercivity for the reference sample is 32 kOe, which is also higher than the FePt(BN, Re, C) film (Hc = 27 kOe), and both films present lower remanence (Mr(parallel)/Mr(perpendicular) = 0.08~0.12), that is, the index for perpendicular magnetic anisotropy. The higher perpendicular magnetization for both films was due to highly (001) textured FePt films, which was also evidenced by the tight rocking width of 4.1°/3.0° for (001)/(002) X-ray diffraction peaks, respectively, and high-enough ordering degree. The reference sample was measured to have a higher ordering degree (S = 0.84) than FePt(BN, Re, C) (S = 0.63). As a result, the Ag segregant shows stronger ability to promote the ordering of the FePt film; however, the FePt(BN, Re, C) film still has comparable magnetic properties without Ag doping. From the surface and elemental composition analysis, the metallic Re atoms found in the FePt lattice result in a strong spin-orbital coupling between transition metal Fe (3d electron) and heavy metals (Re, Pt) (5d electron) and we conducted high magnetocrystalline anisotropy (Ku). Above is the explanation that the lower-ordered FePt(BN, Re, C) film still has high-enough Ku and out-of-plane Hc. Regarding the microstructure, both the reference sample and FePt(BN, Re, C) show granular structure and columnar grains, and the respective average grain size and distributions are 6.60 nm (12.5%) and 11.2 nm (15.9%). The average widths of the grain boundaries and the aspect ratio of the columnar grain height are 2.05 nm, 1.00 nm, 2.35 nm, and 1.70 nm, respectively.

Magnetic properties of (Ni0.81Fe0.19/SiO2)n multilayers for high frequency on-wafer inductor applications

We investigated the magnetic properties of multilayer stacks of Ni81Fe19 thin films separated with SiO2 intended for use in inductors operating at sub-GHz frequencies. We measured saturation magnetization, anisotropy field, coercivity, and complex permeability of sputtered multilayer structures consisting of thin film stacks of 5, 10, 15, 20, and 25 layers, ranging from 160 to 1455 nm in total magnetic material thickness. Our analysis indicates that multilayer stacks composed of repeated layers thinner than 115 nm generally maintained the desired magnetic properties found in individual thin films, such as high permeability, low anisotropy, and low coercive field. Moreover, the multilayer stacks did not exhibit unwanted characteristics such as stripe domain formation and decreased value of real permeability, which commonly occurred in single thicker films. These properties make them suitable for on-wafer inductor applications.

Elevated corrosion resistance and improved magnetic properties of sintered Nd-Fe-B magnets via the infiltration of DyCr film

The low coercivity at high temperature and poor corrosion resistance limit the application field of Nd-Fe-B magnets. In this work, a DyCr film was prepared on the surface of Nd-Fe-B magnet through magnetron sputtering, and then subjected to grain boundary diffusion (GBD) to improve magnetic properties and enhance corrosion resistance. The results show that the residual Cr-rich film exists on the surface of NdFeB magnets, acting as a protective coating to enhance the corrosion resistance, which is evidenced by the weight loss experiment and scanning electron microscopy (SEM) image. Moreover, Cr element in the grain boundary phase increase the electrochemical potential from − 0.985 to − 0.733 V, which is also beneficial in improving corrosion resistance. Transmission electron microscope (TEM) analysis confirmed that the crystal structure of intergranular phase remained unchanged after diffusion, i.e. BCC-RE2O3 (RE=Rare Earth) phase. The coercivity was improved significantly, obtaining an increment of 19.4% comparing to that of initial magnet, which is attributed to the formed Dy-rich shell with high magnetocrystalline anisotropy field and the improved distribution of grain boundary phase. This suggests that it is feasible to fabricate high coercivity magnets and strong corrosion resistance only through grain boundary diffusion, which is expected to further shorten the processing flow of Nd-Fe-B magnets.

High remanence ratio of aluminum substituted hexagonal barium ferrite films for self-biased microwave devices

A high remanence ratio of hexagonal barium ferrite film is urgently needed for self-biased microwave devices. In this work, the aluminum-substituted hexagonal barium ferrite films (BaFe(12−x)AlxO19) with different substituting concentrations (x = 0, 1.5, 2, 2.5, 3) were deposited on the Al2O3 substrate by pulsed laser deposition method using self-sintered BaFe(12−x)AlxO19 target. Firstly, the targets with different Al concentrations were sintered by the solid phase method and exhibited high dense, uniform microstructure, and high purity. Then, the influence of the Al ions concentration on the crystal structure, morphology, and magnetic and microwave properties of BaFe(12−x)AlxO19 films was studied in detail. Structural characterizations confirm that the Al prefers to substitute for 2a, 4f2 and 2b sites and promotes the grain (formed as single-domain) orientation growth, which results in a decrease in the saturation magnetization, an increase of remanence ratio and anisotropy field. Consequently, a high remanence ratio of 95 % was obtained for BaFe(12−x)AlxO19 film at x = 3, and also displays a high anisotropy field (27.7 kOe), a low saturation magnetization (1758 G) and an appropriate ferromagnetic resonance linewidth (～436 Oe), which can be applied in self-biased devices.

Effect of the laser fluence on the microstructure and the relating magnetic properties of BaFe12O19 films grown on YSZ(111) by PLD for optimized perpendicular recording

High-quality BaFe12O19 (BaM) films with high uniaxial anisotropy fields of HA = 17.5 and 18.5 kOe were obtained by pulsed laser deposition (PLD) at two fluences of 1.5 and 5.1 J/cm2 on YSZ(111) substrate, using a platinum interlayer for reducing lattice mismatch. We demonstrated that the microstructure, morphology, and stoichiometry of the hexaferrite BaFe12O19 films can be affected by raising the corresponding energy per pulse from 25 to 75 mJ. However, we also concluded that the increase of fluence leads to the formation of a non-stoichiometric BaM film through two nucleation steps and an output growth of small grains in addition to the increase of the defect density. In turn, this has contributed to the enhancement of the coercive field from Hc = 1769 Oe to Hc = 2166 Oe as it is required for the improvement of perpendicular recording resolution. We found that both the lateral coherent block size and misorientation of mosaic blocks are remarkably affected by the growth kinetics, which itself depends on the energy per pulse. For a deep understanding of the effect of laser fluence on the microstructure, chemical composition, and on the magnetic properties of thin BaM films, the results of complementary methods are combined. These methods comprise high-resolution X-ray diffraction, atomic force microscopy, high-resolution transmission electron microscopy (TEM), scanning TEM combined with energy-dispersive X-ray spectroscopy, and vibrating sample magnetometer.Graphical abstract