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Abstract: The unloaded quality factor of the cavity resonator is the ratio between the stored energy of the cavity resonator to the power loses in the cavity resonator. The homemade rectangular cavity resonator in X-band shows higher unloaded quality factor compare with standard cavity resonator in the TE102 mode. Because the inner walls of rectangular cavity resonator are treated through high quality polishing and high purity Au plating. Also the inner walls are made by printed circuit board which has thin Cu foil, two problems such as mechanical vibration and thermal expansion can be solved by minimizing unwanted eddy current. Through the ferromagnetic resonance measurement by using our rectangular cavity resonator, we can be obtained reasonable values of resonance frequency and linewidth by using NiFe thin film. As a result, the Gilbert damping constant from the experimental result is in good agreement with the typical value of damping parameter of the NiFe thin film. [Copyright &y& Elsevier]

Abstract: Epoxide-containing polycardanol was enzymatically synthesized via two routes using two different enzymes, viz. lipase and peroxidase. Lipase catalysis was used for the epoxidation of the unsaturated alkyl chains of both cardanol and polycardanol. Peroxidase catalysis was used for the polymerization of both cardanol and epoxide-containing cardanol. One route was the synthesis of epoxide-containing cardanol from cardanol, hydrogen peroxide and an organic acid in the presence of lipase, followed by the polymerization of the phenolic functional groups of cardanol using peroxidase. In the other route, polymerized cardanol was prepared from cardanol and hydrogen peroxide in the presence of peroxidase and, subsequently, the epoxide-containing polycardanol was synthesized from polycardanol, hydrogen peroxide and an organic acid in the presence of lipase. NMR and IR spectroscopy confirmed the polymer structure, and the former route yielded epoxide-containing polycardanol in a higher yield of over 90%. The curing of the resulting polymers proceeded thermally at 150°C, yielding transparent polymeric films with a high gloss surface within 3h. The pencil scratch hardness of the present films was improved compared with that of polycardanol. Owing to the epoxide contained in the polymerized cardanol, the film cured with phenalkamine showed a higher hardness value after a relatively short curing time. [Copyright &y& Elsevier]

Abstract: Bisphenol A was polymerized by Coprinus cinereus peroxidase in aqueous 2-propanol solution. Various polymerized products with different molecular weights and hydroxyl values were synthesized depending on the reaction compositions (the ratio of aqueous buffer to 2-propanol). Poly(bisphenol A), a polymer of bisphenol A, was mixed with a diazonaphthoquinone derivative to form a new type of photoresist. A thin photoresist film was formed on the silicon wafer and exposed to UV light for different lengths of time. Poly(bisphenol A) having a molecular weight of approximately 3000 yielded sharply contrasted patterns as compared with the other poly(bisphenol A)s having different molecular weights. [Copyright &y& Elsevier]

Abstract: Chitosan was selectively oxidized at C-6 primary alcohol groups by TEMPO in the presence of sodium hypochlorite (NaOCl) and sodium bromide (NaBr), and also non-specifically oxidized only by NaOCl. Sequentially oxidized chitosan samples from 25 to 100% were produced by 25% increment, from both oxidation processes. By introducing carbonyl groups in chitosan structure with either oxidizing process, the water solubility was shown to be enhancing from all the oxidized sample groups. At the 25% of non-specific oxidation, 0.56% of solubility was detected but there was no proportional increase in solubility as the oxidation level increased. Moreover, the decreases in solubility were observed at 50%-oxidized (0.43%) and 100%-oxidized (0.45%) chitosan samples. During the specific oxidation process, 25%-oxidized 6-oxychitosan had the highest solubility, and the solubility decreased substantially from 0.72 to 0.15% as the degree of oxidation increased from 25 to 100%. Possibly, excessive incorporation of negative charges on chitosan resulted in the aggregation among 6-oxychitosan molecules by charge–charge interactions. The strongest cholic acid-retardation index (CRI, %) of highly soluble 25%-oxidized 6-oxychitosan was consistently observed until 24h of dialysis, which means the CRI is closely related to the water solubility of 6-oxychitosan. Therefore, the solubility improvement should be considered for enhancing the biological activity such as bile acid-binding capacity. Also, it was suggested that negative charge increase in chitosan structure above a certain level led to adverse effect on the binding capacity. [Copyright &y& Elsevier]

Electrical conduction in magnetic materials depends on their magnetization configuration, resulting in various magnetoresistances (MRs). The microscopic mechanisms of MR have so far been attributed to either an intrinsic or extrinsic origin, yet the contribution and temperature dependence of either origin has remained elusive due to experimental limitations. In this study, we independently probed the intrinsic and extrinsic contributions to the anisotropic MR (AMR) of a permalloy film at varying temperatures using temperature-variable terahertz time-domain spectroscopy. The AMR induced by the scattering-independent intrinsic origin was observed to be approximately 1.5% at T = 16 K and is virtually independent of temperature. In contrast, the AMR induced by the scattering-dependent extrinsic contribution was approximately 3% at T = 16 K but decreased to 1.5% at T = 155 K, which is the maximum temperature at which the AMR can be resolved using THz measurements. Our results experimentally quantify the temperature-dependent intrinsic and extrinsic contributions to AMR, which can stimulate further theoretical research to aid the fundamental understanding of AMR. [ABSTRACT FROM AUTHOR]

Enhanced microwave absorption properties were successfully achievable from SrFe 2- x Zn x Fe 16 O 27 (SrFe 2- x Zn x W; x = 0.0, 0.5, 1.0, and 2.0) hexaferrite filler-epoxy resin matrix composites. The composite samples were fabricated with the filler volume fractions (V f) of 30, 50, 70, and 90%. Compared with fully Zn-substituted SrZn 2 W composite (x = 2.0), unsubstituted and partially Zn-substituted SrFe 2- x Zn x W (x = 0.0, 0.5, and 1.0) composites exhibited much higher real and imaginary parts of complex permittivity (ε r), which is attributable to higher electron hopping between Fe2+ and Fe3+ ions, and also slightly higher real and imaginary parts of complex permeability (μ r) due to higher saturation magnetization (M s). Among all samples, a 2.8 mm-thick SrFe 1·5 Zn 0·5 W (x = 0.5) composite with the V f of 90% exhibited the most appropriate for application in the region of 3.4–3.8 GHz, having the minimum reflection loss (RL min) of −46 dB at 3.6 GHz with the bandwidth of 0.43 GHz (3.38–3.81 GHz) below −10 dB, while a 2.15 mm-thick SrFeZnW (x = 1.0) composite with the V f of 70% showed the most appropriate for application in the region of 5.9–7.1 GHz, possessing the RL min value of −23.7 dB at 6.6 GHz with the bandwidth of 1.38 GHz (5.85–7.23 GHz) below −10 dB. Consequently, partially Zn-substituted SrW-type hexaferrites are very promising microwave absorbers for 5G mobile communications in the Ku band (0.5–18 GHz). [ABSTRACT FROM AUTHOR]

Mn-doped sodium iron fluorophosphates Na2Fe0.9Mn0.1PO4F were synthesized using ball milling via a solid-state reaction route. The crystal structure and magnetic properties of the as-prepared materials were studied by using X-ray diffraction (XRD), superconducting quantum interference device (SQUID), and Mössbauer spectroscopy. Structural refinement of Na2Fe0.9Mn0.1PO4F was analyzed using the Fullprof program. From the XRD patterns, the crystal structure was found to be orthorhombic with the space group Pbcn. Na2Fe0.9Mn0.1PO4F has a 2-D layered structure composed of a pair of Fe(Mn)O4F2 octahedrons through fluorine ion sharing, similar to that of Na2FePO4F. The temperature dependence of the zero-field-cooled (ZFC) and field-cooled (FC) curves was measured at temperatures ranging from 1.8 to 295 K under an applied field of 100 Oe. We confirmed that the Néel temperature was 2.5 K, which is lower than that of Na2FePO4F ($T_{N} =3.4$ K). Mössbauer spectroscopy measurements at 4.2–295 K were conducted. At all the temperatures, the spectra were fitted with a double and were determined to be Fe2+ ions based on an isomer shift ($\delta$). In addition, the large value of the electric quadrupole splitting ($\Delta E_{Q}$) is explained by the asymmetric local environment of the Fe ions. [ABSTRACT FROM AUTHOR]

Understanding of ultrafast spin dynamics is crucial for future spintronic applications. In particular, the role of non-thermal electrons needs further investigation in order to gain a fundamental understanding of photoinduced demagnetization and remagnetization on a femtosecond time scale. We experimentally demonstrate that non-thermal electrons existing in the very early phase of the photoinduced demagnetization process play a key role in governing the overall ultrafast spin dynamics behavior. We simultaneously measured the time-resolved reflectivity (TR-R) and the magneto-optical Kerr effect (TR-MOKE) for a Co/Pt multilayer film. By using an extended three-temperature model (E3TM), the quantitative analysis, including non-thermal electron energy transfer into the subsystem (thermal electron, lattice, and spin), reveals that energy flow from non-thermal electrons plays a decisive role in determining the type I and II photoinduced spin dynamics behavior. Our finding proposes a new mechanism for understanding ultrafast remagnetization dynamics. [ABSTRACT FROM AUTHOR]

Time‐resolved magneto‐optical Kerr effect measurement is carried out to determine ultrafast hysteresis behavior during a photo‐induced demagnetization/remagnetization process for Co/Pt ferromagnetic multilayers. Due to the stroboscopic measurement scheme, hysteresis curve measured by a pump–probe technique exhibits an irreversible behavior, repeatedly reset to a metastable hysteresis state at each stroboscopic measurement, observed as the reduction of the coercivity. It is demonstrated that the stroboscopically measured hysteresis and the coercivity could be a stable parameter in describing the ultrafast photo‐induced spin dynamics for both reversible and irreversible behaviors. Moreover, it is found that an unusual coercivity behavior exists together with a nontrivial magnetization change under external fields comparable to the coercivity of the sample. [ABSTRACT FROM AUTHOR]

• Partial substitution of Zn2+ for Fe2+ greatly enhances complex permittivity. • Partial substitution of Zn2+ enhances both saturation magnetization and permeability. • Enhanced permittivity improves impedance matching characteristic for low V f values. • Partial substitution of Zn2+ enhances absorption properties with reduced V f.. A partial substitution of Zn2+ for the Fe2+ site of BaY-type hexaferrite was found to be effective for the improvement of microwave absorption properties in 0.5–18 GHz. For this study, the composites of polycrystalline Ba 2 Fe 2- x Zn x Fe 12 O 22 (Ba 2 Fe 2- x Zn x Y, 0.5 ≤ x ≤ 2.0) and epoxy resin were fabricated with various hexaferrite volume fractions (V f) of 30–90%. As a result, Ba 2 Zn x Fe 2- x Y (x = 0.5–1.5) composites having the partial substitution of Zn2+ exhibited larger complex permittivity values than fully Zn2+ substituted composite of Ba 2 Zn 2 Y (x = 2.0) due to an electron hopping between Fe2+ and Fe3+ ions. Because of the enhanced permittivity, Ba 2 Fe 2- x Zn x Y (x = 0.5–1.5) composites with 30% of V f possessed better impedance matching characteristics compared with other composites having larger V f values. Consequently, Ba 2 Fe 2- x Zn x Y (x = 0.5–1.5) composites exhibited excellent RL values lower than −50 dB with the thickness values ranging from 1.52 to 1.80 mm. [ABSTRACT FROM AUTHOR]

We have experimentally investigated the field- and fluence-dependent terahertz (THz) emission behaviors by a femtosecond optical pump in Co ferromagnetic films, together with the time-resolved magneto-optical Kerr effect measurement. The thickness of Co and Ta capping layers has been systematically varied. For thick films, THz emission behavior is found to be directly matched with the photoinduced ultrafast demagnetization and remagnetization dynamics. The angle-dependent THz emission measurement also confirms a direct relation between the THz emission and the photoinduced demagnetization/remagnetization dynamics in the case of thick films, while THz emission from the inverse spin Hall effect also plays a role in the case of thin Co films. [ABSTRACT FROM AUTHOR]

A low-power spin-torque nano-oscillator (STNO)-based wireless communication is demonstrated with a 180 nm CMOS transmitter and receiver. The ON–OFF keying (OOK) modulation is employed to overcome the inherent drawbacks of the STNO, such as low output power and spectral purity, despite its advantages of a wide frequency tuning range and nano-scale dimensions. As the magnetic-tunnel-junction (MJT) STNO with an MgO barrier has a maximum oscillation power as small as −75 dBm at 3.39 GHz, a 68 dB high-gain amplification throughout the transmitter and receiver is needed for a 1 m wireless communication. A 36 dB high-gain amplifier with a 3.9 dB low noise figure is implemented for the OOK transmitter together with an external modulator. The receiver is composed of a 3.5 dB low-noise amplifier (LNA) with a high gain of 27 dB, gain-boosted envelope detector, and baseband amplifier. The transmitter and receiver amplifiers are implemented with a highly isolated ground between each stage in order to prevent oscillations even at the high gain. The communication system with the STNO achieves an 11.8 Mb/s wireless data transmission over 1 m, with a power consumption of 41.4 mW. The implemented transmitter and receiver occupy 2.34 and 4.08 mm2, including all of the pads, respectively. The proposed system achieves the highest data rate with the lowest power consumption compared to those of the previous state-of-the-art STNO-based wireless communication systems. [ABSTRACT FROM AUTHOR]

Abstract Gilbert damping in nonmagnetic metal (NM)/permalloy (Py)/nonmagnetic metal (NM) trilayers was studied using ferromagnetic resonance (FMR) measurements for different constituent materials (NM = Pt, Ta, Cu, and Ti) of varying Py thickness (t = 2, 3, 4, 5, 6, 8, and 10 nm) fabricated using an ultrahigh vacuum sputtering system. We found that the Gilbert damping constant increases with decreasing Py thickness and varies for different constituents of nonmagnetic metals. For NM = Pt, the damping constant of Py increases with decreasing Py thickness more remarkably than for other nonmagnetic metals. According to quantitative estimations of the effective spin-mixing conductance G eff mix , it was found that the value of G eff mix = 1.17 × 1015 Ω−1·m−2 for Pt is one order of magnitude greater than G eff mix = 0.13 × 1015 Ω−1·m−2 for Cu and 0.11 × 1015 Ω−1·m−2 for Ti. The large G eff mix value for Pt/Py/Pt is known to be caused by the strong spin-orbit coupling (SOC) of Pt. The effective spin-mixing conductance for Pt is 3 times greater than that (0.27 × 1015 Ω−1·m−2) for Ta despite the SOC of both Pt and Ta is similar in magnitude. This work allows not only for an understanding of the interface effect of the Gilbert damping constant on NM/Py/NM trilayers but also for optimal design of low-power-consumption spintronic devices that are composed of a variety of hetero-interfaces between the different magnetic and nonmagnetic layers. [ABSTRACT FROM AUTHOR]

We present the fabrication of ultrathin Ho 3 Fe 5 O 12 (HoIG) films on 111- oriented-Gd 3 Ga 5 O 12 (GGG) via the metal-organic decomposition (MOD) method followed by a sequence annealing process. We characterized the crystal structure, surface morphology, and magnetic properties to study the effect of annealing temperature on the quality of MOD-grown HoIG films. For temperatures higher than 800 ⁰C, we observe the infiltration of Iron (Fe) from the HoIG film into the GGG substrate. In particular, the Fe-diffusion is significantly enhanced for a 1000 ⁰C-annealed sample of which crystal structure and magnetic properties are also affected. For temperatures lower than 800 ⁰C, on the other hand, the smooth surface and strong crystallinity cannot be guaranteed. This suggests that an annealing temperature of 800 ⁰C is the optimal condition for the MOD-grown HoIG film. The quality of the sample is further confirmed by measuring the spin Hall magnetoresistance (SMR) of HoIG/Pt, in which we found the unconventional angular dependence and comparable spin mixing conductance similar to the previous reports in other single crystalline IGs. • Epitaxial HoIG thin films with ultra smooth surfaces (R a = 0.088 nm) and high crystallinity is obtained via MOD method. • The annealing temperature strongly influences the Fe-diffusion from the HoIG film to the GGG substrate. • Compensation characteristic of HoIG film has been destroyed as the annealing temperature is too high. • Canted magnetic moment's structure near the compensation temperature has been confirmed by angular dependence SMR signal. [ABSTRACT FROM AUTHOR]

In this article, we report the fabrication of transition metal (TM Co/Ni) and Nb co-doped SrTiO 3 (Ni 0.06 Nb 0.05 Sr 0.12 Ti 0.16 O 0.61 and Co 0.08 Nb 0.05 Sr 0.11 Ti 0.15 O 0.61 ) thin films of thickness around 1.1 μm on monocrystalline Si (100) substrate by RF sputtering at 350 °C. The as-deposited amorphous films were annealed at 800 °C in vacuum to obtain crystalline structure. The X-ray diffraction studies revealed that the annealed polycrystalline films are having a cubic perovskite structure. The surface and cross-sectional morphologies, grain size, elements and structure of the films were studied by atomic force microscope, scanning and transmission electron microscopes. The microstructure and selected area electron diffraction (SAED processed pattern) also confirms the perovskite structure of the SrTiO 3 . The magnetic behaviour of the films was studied by vibrating sample magnetometry and magneto-optic Kerr measurements. The ferromagnetic responses were observed in both materials at room temperature. [ABSTRACT FROM AUTHOR]

The Inverse Spin Hall Effect (ISHE) voltage induced by spin-pumping was measured in Pt/[nonoxidized or oxidized NiFe] samples. The spectrum shape of the DC voltage signal was well-reproduced by simple Lorentzian functions, which were consistent with the prediction of ISHE in Pt/nonoxidized NiFe sample. On the other hand, the voltage signal from the Pt/oxidized NiFe was significantly decreased in accordance with abnormal ferromagnetic resonance (FMR) behavior. The origin of the ISHE voltage degradation was investigated by the FMR spectrum and X-ray photoelectron spectroscopy (XPS) analyses. The spin-pumping was suppressed by the oxidation of NiFe layer and deficient Pt/NiFe interface. The well-defined ferromagnet and clear interface with a normal spin mixing conductance were experimentally demonstrated to be reasonable spin-pumping. [ABSTRACT FROM AUTHOR]

Highlights: [•] Silica-supported catalysts were prepared by reacting Sn(OMe)2 over pretreated silica. [•] The supported catalysts showed great activity and conversion for PLA production. [•] The immobilization of Sn(OMe)2 did not affect the chemical nature of active sites. [•] The spent catalyst was successfully recovered up to 85% by simple filtration. [Copyright &y& Elsevier]

Abstract: The exchange stiffness constants of 25-nm-thick Co40Fe40B20 films are investigated by Brillouin light scattering. Series of Co40Fe40B20 films is prepared with various Ar gas pressures, and we found that the exchange stiffness constant decreases from 1.41 to 0.98×10−11 1rom 1.41 to 0.98ous Ar gas pressures, and we found that thin stiffness constants are much smaller than CoFe values due to the B atoms, and the dependence of Ar gas pressure is noticeable. Based on our previous theoretical work, the switching current density of spin transfer torque magnetic random access memory is very sensitive on the exchange stiffness constant; it implies that engineering the exchange stiffness constant by the fabrication process is important to reduce switching current density and the dispersion of switching current density. [Copyright &y& Elsevier]

Abstract: We investigate magnetic thermal noise spectra in magnetic tunneling junction with spin transfer torque. The basic structure of the examined magnetic tunneling junction is PtMn/F3/Ru/F2/MgO/F1, where F1,2,3 are ferromagnetic layers. F1 acts as a soft free layer, while PtMn/F3/Ru/F2, an exchange biased synthetic ferrimagnet structure, serves as a fixed reference layer. With the assumption of rigid fixed reference layer, the magnetic thermal noise is only related with the thermal motion of the free layer spins. However, we find additional resonance peaks in the magnetic noise spectra, which correspond to the thermal motion of the reference layer spins. Furthermore, the magnetic noise spectra show intricate field dependences, which are related with the spin dynamics of the reference layer induced by spin transfer torque. [Copyright &y& Elsevier]

Abstract: Spin wave dispersion relations in a ferromagnetic nanowire with and without a domain wall are investigated by means of micromagnetic simulations. We confirm that the spin wave dispersion relation is shifted due to the spin wave Doppler effects, when the spin-transfer torque is applied. We also investigate the position-dependent ferromagnetic resonance spectra in the nanowire and find strong local spin wave interferences because of the formation of the standing wave due to reflections from a domain wall. It is observed that the spacing between the local spin wave constructive interferences is uniform, and it is revealed that the spacing is related with the spin wave Doppler shift. [Copyright &y& Elsevier]

Abstract: A fungal peroxidase from Coprinus cinereus (CiP) was successfully used for oxidative polymerization of cardanol in water–organic solvent mixtures. Cardanol is a phenol derivative from a renewable resource having the meta-substituent of a C15 unsaturated hydrocarbon chain mainly with one to three double bonds. So far, only uneconomic plant peroxidases, such as soybean peroxidase (SBP), have been used to polymerize cardanol. The fungal peroxidase used was easily produced by cultivating C. cinereus, and was purified by ultrafiltration and size exclusion chromatography. The purified peroxidase had a specific activity of 4960U/mg. The CiP-catalyzed polymerization of cardanol was carried out in aqueous/organic solvents. Microbial CiP catalyzed the cardanol polymerization as efficiently as SBP. The structure and molecular weight of the polycardanol produced by CiP were comparable to those produced by SBP. A low reaction temperature of 10 and 15°C produced polycardanol in high yield and the hydrogen peroxide feed rate was found to affect the initial reaction rate and the final conversion. From a practical point of view, it is believed that microbial CiP will be found more useful for the synthesis of a range of polyphenols from renewable resources than plant peroxidases. [Copyright &y& Elsevier]

[Display omitted] • Magnetic coercive fields(Hc) obtained from magnetoresistance at low temperature are modulated by current. • Strong current dependence of weak localization was observed with Hc modulation. • Further analysis using HLN theory reveals that interface-driven magnetic inhomogeneity and corresponding localizations play a role as a bridge between the current and magnetism. A systematic study is conducted on an electrically controlled magnetization in tri-layers containing two layers of ferromagnetic (FM) SrRuO 3 , with antiferromagnetic (AFM) insulating manganites sandwiched in between. Magneto-resistance curves exhibit that a huge weak anti-localization or localization shapes around zero magnetic field and the localization shapes and coercive fields change simultaneously by currents. This results propose that interface-driven magnetic inhomogeneity such as the FM clusters embedded in the AFM matrix, and corresponding localizations play a role as a bridge between the current and magnetism. The results suggest that interfacial magnetism can cause new functions in a heterostructure, leading to an expansion of research subjects of current-controlled magnetism. [ABSTRACT FROM AUTHOR]

We report a universal terahertz (THz) emission behavior from simple Ni, Fe, and Co metallic ferromagnetic films, triggered by the femtosecond laser pulse and subsequent photoinduced demagnetization on an ultrafast time scale. THz emission behavior in ferromagnetic films is found to be consistent with initial magnetization states controlled by external fields, where the hysteresis of the maximal THz emission signal is observed to be well-matched with the magnetic hysteresis curve. It is experimentally demonstrated that the ultrafast THz emission by the photoinduced demagnetization is controllable in a simple way by external fields as well as pump fluences. [ABSTRACT FROM AUTHOR]

Spin pumping and the spin transfer torque in the normal metal (NM)/ferromagnetic materials (FM) heterostructure strongly depend on the interfacial spin memory loss. Therefore, the interface engineering of the NM/FM bilayer is important for enhancing spin pumping and spin-orbit torque efficiency for spin-orbitronic devices. In this study, we investigate the influence of the graphene interlayer between Pt and yttrium iron garnet (YIG) on spin pumping. Measurements of both the coplanar wave guide ferromagnetic resonance and inverse spin Hall effect with ferromagnetic resonance are performed to study the role of graphene in the transmission of the spin current at the interface. Results indicate a decreased Gilbert damping constant with the insertion of graphene interlayer, which causes the spin mixing conductance and inverse spin Hall voltage to be significantly reduced. The observed decrease in damping constant and spin injection is attributed to the presence of magnetic proximity effect and interfacial spin-orbit scattering, which causes graphene to serve as a spin-sink layer. Image 1 • Introduction of graphene interlayer between Pt and yttrium iron garnet (YIG) heterostructures. • Investigation of interface engineering by ferromagnetic resonance and inverse spin Hall voltage measurements. • Reduction of spin mixing conductance and the inverse spin Hall voltage by the insertion of a graphene layer. • Graphene at the interface of Pt/YIG behaves as a spin-sink layer. [ABSTRACT FROM AUTHOR]

Quantum computers now encounter the significant challenge of scalability, similar to the issue that classical computing faced previously. Recent results in high-fidelity spin qubits manufactured with a Si CMOS technology, along with demonstrations that cryogenic CMOS-based control/readout electronics can be integrated into the same chip or die, opens up an opportunity to break out the challenges of qubit size, I/O, and integrability. However, the power consumption of cryogenic CMOS-based control/readout electronics cannot support thousands or millions of qubits. Here, we show that III-V two-dimensional electron gas and Nb superconductor-based cryogenic electronics can be integrated with Si and operate at extremely low power levels, enabling the control and readout for millions of qubits. Our devices offer a unity gain cutoff frequency of 601 GHz, a unity power gain cutoff frequency of 593 GHz, and a low noise indication factor I D g m - 1 of 0.21 Vmm S - 1 at 4 K using more than 10 times less power consumption than CMOS., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The transition between the ferromagnetic (FM) and anti-ferromagnetic (AFM) phases in van der Waals (vdW) magnets has been extensively studied since the discovery of vdW magnets, due to the importance of both transitions within a single material. Recently, among vdW magnets, Fe 3 GaTe 2 (FGaT) has garnered significant attention for its robust FM properties that remain stable above room temperature. Also, the FM to AFM phase transition in this material has been achieved through substitutional Co-atom doping at Fe sites. Here, we have reconfirmed the FM to AFM phase transition in FGaT and observed the metamagnetic transition between the two magnetic phases. Furthermore, the meta-stable magnetic state in 19-22% Co-doped FGaT in a certain field range was noted, which vanishes when the doping level increases further. Interestingly, when measuring the minor loop during the phase transition, its magnetization under a field-sweep reversing field is maintained in a meta-stable magnetic state region. The persistence of magnetization, which indicates the co-existence of AFM and FM domains in this meta-stable magnetic region, creates multi-level configurations that enable advanced applications in multi-level logic devices, neuromorphic computing, and applications involving magnetic domains. Our findings can expand the application scope and the utilization methods of vdW magnets.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), emerged as a global outbreak in 2019, profoundly affecting both human health and the global economy. Various vaccine modalities were developed and commercialized to overcome this challenge, including inactivated vaccines, mRNA vaccines, adenovirus vector-based vaccines, and subunit vaccines. While intramuscular vaccines induce high IgG levels, they often fail to stimulate significant mucosal immunity in the respiratory system. We employed the Newcastle disease virus (NDV) vector expressing the spike protein of the SARS-CoV-2 Beta variant (rK148/beta-S), and evaluated the efficacy of intranasal vaccination with rK148/beta-S in K18-hACE2 transgenic mice. Intranasal vaccination with a low dose (10 6.0 EID 50 ) resulted in an 86% survival rate after challenge with the SARS-CoV-2 Beta variant. Administration at a high dose (10 7.0 EID 50 ) led to a reduction in lung viral load and 100% survival against the SARS-CoV-2 Beta and Delta variants. A high level of the SARS-CoV-2 spike-specific IgA was also induced in vaccinated mice lungs following the SARS-CoV-2 challenge. Our findings suggest that rK148/beta-S holds promise as an intranasal vaccine candidate that effectively induces mucosal immunity against SARS-CoV-2.

The recent discovery of room-temperature ferromagnetism in 2D van der Waals (vdW) materials, such as Fe 3 GaTe 2 (FGaT), has garnered significant interest in offering a robust platform for 2D spintronic applications. Various fundamental operations essential for the realization of 2D spintronics devices are experimentally confirmed using these materials at room temperature, such as current-induced magnetization switching or tunneling magnetoresistance. Nevertheless, the potential applications of magnetic skyrmions in FGaT systems at room temperature remain unexplored. In this work, the current-induced generation of magnetic skyrmions in FGaT flakes employing high-resolution magnetic transmission soft X-ray microscopy is introduced, supported by a feasible mechanism based on thermal effects. Furthermore, direct observation of the current-induced magnetic skyrmion motion at room temperature in FGaT flakes is presented with ultra-low threshold current density. This work highlights the potential of FGaT as a foundation for room-temperature-operating 2D skyrmion device applications., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

Interfacial magnetic interactions between different elements are the origin of various spin-transport phenomena in multi-elemental magnetic systems. We investigate the coupling between the magnetic moments of the rare-earth, transition-metal, and heavy-metal elements across the interface in a GdFeCo/Pt thin film, an archetype system to investigate ferrimagnetic spintronics. The Pt magnetic moments induced by the antiferromagnetically aligned FeCo and Gd moments are measured using element-resolved x-ray measurements. It is revealed that the proximity-induced Pt magnetic moments are always aligned parallel to the FeCo magnetic moments, even below the ferrimagnetic compensation temperature where FeCo has a smaller moment than Gd. This is understood by a theoretical model showing distinct effects of the rare-earth Gd 4f and transition-metal FeCo 3d magnetic moments on the Pt electronic states. In particular, the Gd and FeCo work in-phase to align the Pt moment in the same direction, despite their antiferromagnetic configuration. The unexpected additive roles of the two antiferromagnetically coupled elements exemplify the importance of detailed interactions among the constituent elements in understanding magnetic and spintronic properties of thin film systems., (© 2024. The Author(s).)

The gut microbiota plays a pivotal role in metabolic disorders, notably type 2 diabetes mellitus (T2DM). In this study, we investigated the synergistic potential of combining the effects of Bifidobacterium longum NBM7-1 (CKD1) with anti-diabetic medicines, Lobeglitazone Ⓡ (LO), Sitagliptin Ⓡ (SI), and Metformin Ⓡ (Met), to alleviate hyperglycemia in a diabetic mouse model. CKD1 effectively mitigated insulin resistance, hepatic steatosis, and enhanced pancreatic β-cell function, as well as fortifying gut-tight junction integrity. In the same way, SI-CKD1 and Met- CKD1 synergistically improved insulin sensitivity and prevented hepatic steatosis, as evidenced by the modulation of key genes associated with insulin signaling, β-oxidation, gluconeogenesis, adipogenesis, and inflammation by qRT-PCR. The comprehensive impact on modulating gut microbiota composition was observed, particularly when combined with Metformin Ⓡ . This combination induced an increase in the abundance of Rikenellaceae and Alistipes related negatively to the T2DM incidence while reducing the causative species of Cryptosporangium, Staphylococcaceae , and Muribaculaceae . These alterations intervene in gut microbiota metabolites to modulate the level of butyrate, indole-3-acetic acid, propionate, and inflammatory cytokines and to activate the IL-22 pathway. However, it is meaningful that the combination of B. longum NBM7-1(CKD1) reduced the medicines' dose to the level of the maximal inhibitory concentrations (IC50). This study advances our understanding of the intricate relationship between gut microbiota and metabolic disorders. We expect this study to contribute to developing a prospective therapeutic strategy modulating the gut microbiota.

Vanadium dioxide (VO 2 ) is one of the strongly correlated materials exhibiting a reversible insulator-metal phase transition accompanied by a structural transition from a low-temperature monoclinic phase to high-temperature rutile phase near room temperature. Due to the dramatic change in electrical resistance and optical transmittance of VO 2 , it has attracted considerable attention towards the electronic and optical device applications, such as switching devices, memory devices, memristors, smart windows, sensors, actuators, etc. The present review provides an overview of several methods for the synthesis of nanostructured VO 2 , such as solution-based chemical approaches (sol-gel process and hydrothermal synthesis) and gas or vapor phase synthesis techniques (pulsed laser deposition, sputtering method, and chemical vapor deposition). This review also presents stoichiometry, strain, and doping engineering as modulation strategies of physical properties for nanostructured VO 2 . In particular, this review describes ultraviolet-visible-near infrared photodetectors, optical switches, and color modulators as optical sensing applications associated with nanostructured VO 2 materials. Finally, current research trends and perspectives are also discussed.

The interplay between ferromagnetism and the non-trivial topology has unveiled intriguing phases in the transport of charges and spins. For example, it is consistently observed the so-called topological Hall effect (THE) featuring a hump structure in the curve of the Hall resistance (R xy ) vs. a magnetic field (H) of a heterostructure consisting of a ferromagnet (FM) and a topological insulator (TI). The origin of the hump structure is still controversial between the topological Hall effect model and the multi-component anomalous Hall effect (AHE) model. In this work, we have investigated a heterostructure consisting of Bi x Sb 2-x Te y Se 3-y (BSTS) and Cr 2 Te 3 (CT), which are well-known TI and two-dimensional FM, respectively. By using the so-called "minor-loop measurement", we have found that the hump structure observed in the CT/BSTS is more likely to originate from two AHE channels. Moreover, by analyzing the scaling behavior of each amplitude of two AHE with the longitudinal resistivities of CT and BSTS, we have found that one AHE is attributed to the extrinsic contribution of CT while the other is due to the intrinsic contribution of BSTS. It implies that the proximity-induced ferromagnetic layer inside BSTS serves as a source of the intrinsic AHE, resulting in the hump structure explained by the two AHE model., (© 2023. The Author(s).)

We investigate the effects of interfacial oxidation on the perpendicular magnetic anisotropy, magnetic damping, and spin-orbit torques in heavy-metal (Pt)/ferromagnet (Co or NiFe)/capping (MgO/Ta, HfO x , or TaN) structures. At room temperature, the capping materials influence the effective surface magnetic anisotropy energy density, which is associated with the formation of interfacial magnetic oxides. The magnetic damping parameter of Co is considerably influenced by the capping material (especially MgO) while that of NiFe is not. This is possibly due to extra magnetic damping via spin-pumping process across the Co/CoO interface and incoherent magnon generation (spin fluctuation) developed in the antiferromagnetic CoO. It is also observed that both antidamping and field-like spin-orbit torque efficiencies vary with the capping material in the thickness ranges we examined. Our results reveal the crucial role of interfacial oxides on the perpendicular magnetic anisotropy, magnetic damping, and spin-orbit torques.

Among two-dimensional (2D) layered van der Waals materials, ferromagnetic 2D materials can be useful for compact low-power spintronic applications. One promising candidate material is Fe 3 GeTe 2 (FGT), which has a strong perpendicular magnetic anisotropy and relatively high Curie temperature. In this study, we confirmed that an oxide layer (O-FGT) naturally forms on top of exfoliated FGT and that an antiferromagnetic coupling (AFC) exists between FGT and O-FGT layers. From a first-principles calculation, oxide formation at the interface of each layer induces an AFC between the layers. An AFC causes a tailed hysteresis loop, where two-magnetization reversal curves are included, and a negative remanence magnetization at a certain temperature range.

2,2,6,6-Tetramethyl-1-piperidine oxoammonium ion (TEMPO)-mediated oxidation was applied to oat beta-glucans, and the physicochemical and hypocholesterolemic properties of the resulting derivatives were investigated. The (13)C NMR spectra revealed that C6 primary alcohol groups were selectively oxidized into carboxyl groups. The oxidized derivatives exhibited enhanced water solubility and improved in vitro bile acid binding capacity. When hypercholesterolemic rats were fed diets containing the oxidized beta-glucan, the levels of triglyceride, total cholesterol, LDL-C, and VLDL-C in the rats significantly decreased (p < 0.05), consequently improving the serum lipid profiles. Dietary supplementation with beta-glucans reduced also the total cholesterol level in liver. Furthermore, more fecal eliminations of total cholesterol and triglyceride were observed, which were favorably correlated to their reduced levels in the serum and liver. As a result, oxidized oat beta-glucan exhibits potential use as an active cholesterol-lowering ingredient.