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The influence of magnetocrystalline anisotropy (MCA) on antiferromagnetism is elucidated through the characterization of the spin‒flop transition. However, due to a lack of suitable candidates for investigation, a detailed understanding of the preservation of the spin‒flop transition in the presence of low MCA energy remains elusive. In this study, we introduce CrPS4, which is a two-dimensional van der Waals antiferromagnet, as an ideal system to explore the exceedingly weak limit of the thermally-evolved MCA energy. By employing a uniaxially anisotropic spin model and fitting it to the experimental magnetic properties, we quantify the MCA energy and identify the discernible spin configurations in different magnetic phases. Notably, even at the limit of extremely weak MCA, with a mere 0.12% of the interlayer antiferromagnetic exchange interaction at T = 33 K, which is slightly below the Néel temperature (TN) of 38 K, the spin‒flop transition remains intact. We further establish a direct correlation between the visualized spin arrangements and the progressive reversal of magnetic torque induced by rotating magnetic fields. This analysis reveals the essential role of MCA in antiferromagnetism, thus extending our understanding to previously undetected limits and providing valuable insights for the development of spin-processing functionalities based on van der Waals magnets. Though the impact of magnetic anisotropy on antiferromagnetism is manifested in spin-flop transition, understanding the preservation of this transition in weak anisotropy remains elusive. By adopting an anisotropic spin model, we find that the spin-flop transition remains intact in extremely weak anisotropy, with a mere 0.12% of interlayer exchange interaction at 33 K, slightly below the Néel temperature of 38 K. We further establish a direct relationship between the visualized spin arrangements and the progressive reversal of magnetic torque in rotating magnetic fields. Our analysis provides valuable insights for exploring novel phenomena in the realm of low-dimensional magnetism. [ABSTRACT FROM AUTHOR]

Next‐generation displays require tiny pixel sizes and are applied to AR/VR and holograms. Conventional color filters have limitations in miniaturization and shows poor reliability from heat, light and other environment. Meta‐surface color filters (MCFs) are one of the solutions to replace conventional color filters, suitable for high‐resolution displays. Structural design parameters are adjusted to determine the filtering properties of the MCFs. In addition, the metal based meta‐surface shows better durability cause of the intrinsic characteristics of the material. However, if the structure is complicated, there require many case‐ studies for verification, which increases trial and error. In addition, resonance by phase matching between structures changes according to the angle of incident light. In this study, we suggest a method to reduce the trial and error required in designing structure. Also, the design parameters of the MCFs of the desired color was extracted through an AI model capable of reverse design. Furthermore, we propose a novel MCFs that shows characteristics independent to the angle of incident light through a coaxial hole and disk array structure. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is crucial in examining suitable materials for magnetic functionalities because it affects their magnetic characteristics. In this study, disordered-perovskite RCr0.5Fe0.5O3 (R = Gd, Er) single crystals were synthesized and the influence of magnetic anisotropy and additional ordering of rare-earth moments on cryogenic magnetocaloric properties was investigated. Both GdCr0.5Fe0.5O3 (GCFO) and ErCr0.5Fe0.5O3 (ECFO) crystallize in an orthorhombic Pbnm structure with randomly distributed Cr3+ and Fe3+ ions. In GCFO, the long-range order of Gd3+ moments emerges at a temperature of TGd (the ordering temperature of Gd3+ moments) = 12 K. The relatively isotropic nature of large Gd3+ moment originating from zero orbital angular momentum exhibits giant and virtually isotropic magnetocaloric effect (MCE), with a maximum magnetic entropy change of Δ S M ≈ 50.0 J/kg·K. In ECFO, the highly anisotropic magnetizations result in a large rotating MCE characterized by a rotating magnetic entropy change Δ S θ = 20.8 J/kg·K. These results indicate that a detailed understanding of magnetically anisotropic characteristics is the key for exploring improved functional properties in disordered perovskite oxides. [ABSTRACT FROM AUTHOR]

A helimagnet comprises a noncollinear spin structure formed by competing exchange interactions. Recent advances in antiferromagnet-based functionalities have broadened the scope of target materials to include noncollinear antiferromagnets. However, a microscopic understanding of the magnetic anisotropy associated with the intricate evolution of noncollinear spin states has not yet been accomplished. Here, we have explored the anisotropic magnetic aspects in a layered helimagnet of EuCo2As2 by measuring the magnetic field and angle dependence of the magnetic torque. By adopting an easy-plane anisotropic spin model, we can visualize the detailed spin configurations that evolve in the presence of rotating magnetic fields. This is directly related to the two distinctive magnetic phases characterized by the reversal of the magnetic torque variation across the helix-to-fan transition. Our advanced approach provides an in-depth understanding of the anisotropic properties of noncollinear-type antiferromagnets and a useful guidance for potential applications in spin-processing functionalities. Antiferromagnetic systems are prospective materials for spintronic applications due to increased stability and speed of the magnetisation dynamics. Here, the authors use torque magnetometry and an easy-plane anisotropic model to investigate and understand the magnetic anisotropy of the non-collinear antiferromagnet EuCo2As2. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Metasurface‐based color filter have been regarded as good alternatives of conventional color filter causes of their reliability, simple design method, and high resolved pixelization performance. In this study, we designed a novel metasurface‐based color filter with surface plasmons (SPs). The conventional plasmonic color filters (PCFs) have broad transmittance spectra. Consequently, the color purity degrades and this become a fatal issue for practical use. In order to solve the poor wavelength selectivity of the PCFs, we designed a novel PCF integrated with the Fabry‐Perot interferometer (FPI). We added the simple cavity structure over the matching layer of the existing PCF to apply FPI to the PCF. By applying it, the red tail in the long wavelength band of the transmission properties of PCFs were reduced. The color gamut of the suggested filter has increased 2.42 times compared to the conventional PCFs. These improvements are showed the applicability of PCF to various imaging devices. [ABSTRACT FROM AUTHOR]

Double-perovskite multiferroics have been investigated because alternating orders of magnetic ions act as distinct magnetic origins for ferroelectricity. In Yb2CoMnO6, the frustrated antiferromagnetic order emerging at TN = 52 K induces ferroelectric polarization perpendicular to the c axis through cooperative O2− shifts via the symmetric exchange striction. In our detailed measurements of the magnetoelectric properties of single-crystalline Yb2CoMnO6, we observe full ferromagnetic-like hysteresis loops that are strongly coupled to the dielectric constant and ferroelectric polarization at various temperatures below TN. Unlike Lu2CoMnO6 with non-magnetic Lu3+ ions, we suggest the emergence of additional ferroelectric polarization along the c axis below the ordering temperature of magnetic Yb3+ ions, TYb ≈ 20 K, based on the spin structure established from recent neutron diffraction experiments. While the proposed description for additional ferroelectricity, ascribed to the symmetric exchange striction between Yb3+ and Co2+/Mn4+ magnetic moments, is clearly given, anomalies of dielectric constants along the c axis are solely observed. Our interesting findings on magnetoelectric hysteresis and the possible development of additional ferroelectricity reveal notable characteristics of double perovskites and provide essential guidance for the further examination of magnetoelectric functional properties. [ABSTRACT FROM AUTHOR]

Double-perovskite multiferroics have been investigated because alternating orders of magnetic ions act as distinct magnetic origins for ferroelectricity. In Yb2CoMnO6, the frustrated antiferromagnetic order emerging at TN = 52 K induces ferroelectric polarization perpendicular to the c axis through cooperative O2− shifts via the symmetric exchange striction. In our detailed measurements of the magnetoelectric properties of single-crystalline Yb2CoMnO6, we observe full ferromagnetic-like hysteresis loops that are strongly coupled to the dielectric constant and ferroelectric polarization at various temperatures below TN. Unlike Lu2CoMnO6 with non-magnetic Lu3+ ions, we suggest the emergence of additional ferroelectric polarization along the c axis below the ordering temperature of magnetic Yb3+ ions, TYb ≈ 20 K, based on the spin structure established from recent neutron diffraction experiments. While the proposed description for additional ferroelectricity, ascribed to the symmetric exchange striction between Yb3+ and Co2+/Mn4+ magnetic moments, is clearly given, anomalies of dielectric constants along the c axis are solely observed. Our interesting findings on magnetoelectric hysteresis and the possible development of additional ferroelectricity reveal notable characteristics of double perovskites and provide essential guidance for the further examination of magnetoelectric functional properties. [ABSTRACT FROM AUTHOR]

We fabricated organic light-emitting diodes (OLEDs) with electron injection layers (EILs) and hole blocking layers (HBLs) made from different sized zinc oxide (ZnO) nanoparticles (NPs) made from indium tin oxide (ITO)/poly(3,4-ethylene dioxythiophene):poly (styrenesulfonate) (PEDOT:PSS)/poly(N′,N′-bis(4-butylphenyl)-N′,N′-bis(phenyl)-benzidine) (poly-TPD)/poly(9-vinylcarbazole) (PVK):tris(2-phenylquinoline)iridium(III) (Ir(2-phq)3)/ZnO NPs/Al. We made OLEDs with ZnO NPs with sizes of 5, 10, and 15 nm, and investigated the relationship between the size of the ZnO NPs and the luminance of the OLEDs. The luminance onset voltage is defined as the voltage required to generate a luminance of 1 cd/m2. The OLEDs with ZnO NPs with sizes of 5, 10, and 15 nm had luminance onset voltages of 3.1, 4.1, and 5.3 V, respectively, and luminances of the OLEDs with the ZnO NP sizes of 5, 10, and 15 nm were, respectively, 455.1, 194.4, and 34.8 cd/m2 at 8 V. The OLED with 5 nm ZnO NPs had the lowest luminance onset voltage and highest luminance. This indicates that the Auger electron effect which induces an energy up-conversion process occurred in the OLED with 5 nm ZnO NPs. [ABSTRACT FROM AUTHOR]

This paper reports a new method for fabrication of microlens arrays using a polyoxymethylene (POM) mold with concave-type cylindrical holes prepared by mechanical-micro milling without photolithography and wet etching processes. Microlens arrays were fabricated by a replica molding process using the concave-type POM mold. A polymethylmethacrylate (PMMA) thin film was deposited onto the POM mold and a concave PMMA template was prepared by blowing a nitrogen gas stream onto the thin PMMA film suspended on the micro POM mold. Microlens arrays were fabricated by pouring ultraviolet (UV)-epoxy onto the concave PMMA template and curing the UV-epoxy under UV light. Two types of microlens arrays, one with a hemispherical structure and one with a truncated-cone-type structure, were fabricated. After attaching the hemispherical microlens array onto organic light-emitting diodes (OLEDs), the external quantum efficiency (EQE) of the OLEDs was enhanced by approximately 56.5%. This work provides a valuable method for easy fabrication of microlens arrays with diameters of several hundred micrometers. [ABSTRACT FROM AUTHOR]

A persistent problem with solution processes is dissolution of the first deposited layer by the solution of the second deposited layer. Because the energy barrier between the highest occupied molecular orbital (HOMO) levels of Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-s-butylphenyl)diphenylamine)] (TFB) used as a first hole transporting layer (HTL) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) used as a light-emitting layer (EML) is so large, poly(N-vinylcarbazole) (PVK) was inserted as a second HTL between TFB and F8BT to facilitate hole injection from the TFB layer into the F8BT layer. In this paper, we demonstrate the effect of bilayer HTLs in solution-processed organic light-emitting diodes (OLEDs) using thermally-annealed TFB. The characteristics of OLEDs with HTLs, with and without thermally annealed TFB, are compared. The maximum external quantum efficiency (EQE) of an OLED, with thermally-annealed TFB and spin-coated PVK on the TFB used as bilayer HTLs, increases significantly to 0.617%, whereas the EQE of the OLED, without thermally annealed TFB and PVK spin-coated directly on the as-coated TFB, is greatly reduced to 0.195%. This result indicates that insertion of PVK between thermally annealed TFB and F8BT layers can facilitate easy hole injection from the TFB layer into the F8BT layer and enhance OLED performance. [ABSTRACT FROM AUTHOR]

Yttria-stabilized zirconia (3Y-TZP) containing 0.25% Al2O3, which is resistant to low temperature degradation (LTD), was aged for 10 h at 130–220 °C in air. The aged specimens were subsequently indented at loads ranging from 9.8 to 490 N using a Vickers indenter. The influence of preaging temperature on the biaxial strength of the specimens was investigated to elucidate the relationship between the extent of LTD and the strength of zirconia restorations that underwent LTD. The indented strength of the specimens increased as the preaging temperature was increased higher than 160 °C, which was accompanied by extensive t-ZrO2 (t) to m-ZrO2 (m) and c-ZrO2 (c) to r-ZrO2 (r) phase transformations. The influence of preaging temperature on the indented strength was rationalized by the residual stresses raised by the t→m transformation and the reversal of tensile residual stress on the aged specimen surface due to the indentation. The results suggested that the longevity of restorations would not be deteriorated if the aged restorations retain compressive residual stress on the surface, which corresponds to the extent of t→m phase transformation less than 52% in ambient environment. [ABSTRACT FROM AUTHOR]

Fifteen participants (9 male, 6 female) received a total of 15 monolithic single restorations made from fully sintered (Y, Nb)-TZP (tetragonal zirconia polycrystal) block. The restorations were clinically evaluated for survival, success rate, and periodontal probing depths 6 months after the insertion of the restorations. Esthetic, functional, and biological evaluations were also performed over a 6-month follow-up period. The survival and success rates of the single-unit restorations were 100%. The periodontal probing depth values ranged from 1 to 3 mm. No complications with regard to functional and biological properties were observed after 6 months. The postoperative sensitivity was only a transient phenomenon. The fully sintered (Y, Nb)-TZP single-unit restoration showed highly acceptable quality with successful clinical performance over 6 months. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

Spin-flip transition can occur in antiferromagnets with strong magnetocrystalline anisotropy, inducing a significant modification of the anisotropic magnetic properties through phase conversion. In contrast to ferromagnets, antiferromagnets have not been thoroughly examined in terms of their anisotropic characteristics. We investigated the magnetic-field and angle-dependent magnetic properties of Ising-type antiferromagnetic Ca0.9Sr0.1Co2As2 using magnetic torque measurements. An A-type antiferromagnetic order emerges below TN = 97 K aligned along the magnetically easy c-axis. The reversal of the angle-dependent torque across the spin-flip transition was observed, revealing the strong influence of the magnetocrystalline anisotropy on the magnetic properties. Based on the easy-axis anisotropic spin model, we theoretically generated torque data and identified specific spin configurations associated with the magnetic torque variation in the presence of a rotating magnetic field. Our results enrich fundamental and applied research on diverse antiferromagnetic compounds by shedding new light on the distinct magnetic features of the Ising-type antiferromagnet. [ABSTRACT FROM AUTHOR]

A helimagnet comprises a noncollinear spin structure formed by competing exchange interactions. Recent advances in antiferromagnet-based functionalities have broadened the scope of target materials to include noncollinear antiferromagnets. However, a microscopic understanding of the magnetic anisotropy associated with the intricate evolution of noncollinear spin states has not yet been accomplished. Here, we have explored the anisotropic magnetic aspects in a layered helimagnet of EuCo2As2 by measuring the magnetic field and angle dependence of the magnetic torque. By adopting an easy-plane anisotropic spin model, we can visualize the detailed spin configurations that evolve in the presence of rotating magnetic fields. This is directly related to the two distinctive magnetic phases characterized by the reversal of the magnetic torque variation across the helix-to-fan transition. Our advanced approach provides an in-depth understanding of the anisotropic properties of noncollinear-type antiferromagnets and a useful guidance for potential applications in spin-processing functionalities. Antiferromagnetic systems are prospective materials for spintronic applications due to increased stability and speed of the magnetisation dynamics. Here, the authors use torque magnetometry and an easy-plane anisotropic model to investigate and understand the magnetic anisotropy of the non-collinear antiferromagnet EuCo2As2. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of surface treatments and repair materials on the shear bond strength and to measure the fracture toughness of CAD/CAM provisional restoration materials., Materials and Methods: Four CAD/CAM (3D printing: Nextdent C&B and ZMD-1000B Temporary, CAD/CAM resin block: Yamahachi PMMA disk and Huge PMMA block) and four conventional (monometacrylate: Jet and Alike, dimetacrylate: Luxatemp and Protemp 4) materials were selected to fabricate disk-shaped specimens and divided into six groups according to surface treatment (n=10). CAD/CAM materials were repaired with Jet or Luxatemp, while conventional materials were repaired with their own materials. The shear bond strength was measured by using universal testing machine. Ten rectangular column-shaped specimens for each material were fabricated to measure the fracture toughness by single edge v notched beam technique. Statistical analysis was performed by one-way ANOVA., Results: The highest shear bond strength of CAD/CAM materials was achieved by SiC paper + sandblasting. It was also accomplished when repairing 3D printing materials with Luxatemp, and repairing CAD/CAM resin blocks with Jet. Yamahachi PMMA disk showed the highest fracture toughness. Nextdent C&B showed the lowest fracture toughness value but no statistically significant difference from Alike and Luxatemp ( P >.05)., Conclusion: In order to successfully repair the CAD/CAM provisional restoration, mechanical surface treatment and appropriate repair material according to the CAD/CAM material type should be selected. The CAD/CAM provisional materials have proper mechanical properties for clinical use as compared to conventional materials.