Article
Nanoscience & Nanotechnology
Yu Wang, Yunlai Deng, Qingsong Dai, Keda Jiang, Jiqiang Chen, Xiaobin Guo
Summary: Two high Fe containing Al-Mg-Si-Mn-Fe alloys were prepared and compared with a common applied alloy in terms of microstructures and mechanical properties. The alloys showed a good combination of strength and elongation, mainly due to precipitation and solid solution strengthening from appropriate proportions of Mg and Si elements.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Wenhe Wu, Guangsheng Wei, Bohan Tian
Summary: This study analyzed the reaction mechanism between CO2 and Fe-Si/Mn/Al-C melt at 1600 degrees C, finding that during the early stages of smelting, CO2 released carbon and oxygen into the melt. After reaching the critical composition of the melt, CO2 stopped releasing carbon into the melt, while continuing to decompose and release oxygen atoms, resulting in the oxidation of the alloy and carbon elements in the melt. Additionally, the study also investigated the reaction between CO as the bottom-blowing gas and the Fe-Si/Mn/Al-C melt, which confirmed the partial dissolution of CO generated by the decomposition of CO2 released carbon from the melt.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Shiwei Pan, Feng Qian, Chunan Li, Zidong Wang, Yanjun Li
Summary: This study investigates the influence of adding Zr to AA3003 alloy on precipitation hardening and heat resistance. By optimizing heat treatment processes, a microstructure with superior dispersoid strengthening, thermal stability, and increased yield strength was achieved. The enhanced precipitation kinetics of Al3Zr in the alloy, attributed to the Si content, contributes to the stable strength during isothermal aging at 400 degrees C.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Multidisciplinary
Cheng-Chieh Lin, Ting-Ran Liu, Sin-Rong Lin, Karunakara Moorthy Boopathi, Chun-Hao Chiang, Wen-Yen Tzeng, Wan-Hsiu Chang Chien, Hua-Shu Hsu, Chih-Wei Luo, Hui-Ying Tsai, Hsin-An Chen, Pai-Chia Kuo, Jessie Shiue, Jau-Wern Chiou, Way-Faung Pong, Chia-Chun Chen, Chun-Wei Chen
Summary: Spin-polarized electrons in CsPbBr3 halide perovskite nanoplates (NPLs) can be manipulated by doping manganese cations (Mn2+) and applying an external magnetic field, leading to improved photocatalytic CO2 reduction reaction (CO2RR) efficiencies. The photocatalytic CO2RR of Mn-doped CsPbBr3 NPLs is significantly enhanced by applying an external magnetic field, resulting in prolonged carrier lifetime and suppressed charge recombination.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Yuliu You, Jungki Kim, Cees Kwakernaak, Johannes C. Brouwer, Ruud Westerwaal, Willem G. Sloof
Summary: The surface oxidation and wettability of Mn and Si-alloyed steel after annealing at different conditions were studied. The oxides formed were predicted based on thermodynamic calculations. The contact angle of Pb on the steel surfaces decreased with increasing dew point, indicating an improved wettability.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Takeshi Seki, Yong-Chang Lau, Satoshi Iihama, Koki Takanashi
Summary: The study evaluated the self-induced spin-orbit torque in a single ferromagnetic layer, showing that spin-torque ferromagnetic resonance was present in thin Ni-Fe layers with both asymmetric and symmetric Py layers, while the dampinglike torque was observed only in asymmetric Py layers with thickness <= 3 nm.
Article
Chemistry, Multidisciplinary
Cuiju Yu, Qingqing Feng, Xingxing Li, Jinlong Yang
Summary: This study reveals the significant influence of the spinterface between magnetic electrodes and molecules on spin filtering efficiency through first-principles calculations. The results show that interface configurations can modulate and reverse the spin polarization of tunnelling electrons. The performance of single molecule spintronic devices, such as the spin filtering channel, can be flexibly tuned through suitable interface design.
Article
Engineering, Civil
Xiang-Lin Gu, Zhen-Yu Chen, Qian-Qian Yu, Elyas Ghafoori
Summary: This study investigated the stress recovery behavior of an Fe-Mn-Si-Cr-Ni-VC shape memory alloy for prestressed strengthening. The effects of different prestrain levels, activation temperatures, and initial preloads on recovery stress were evaluated to propose an optimum activation strategy. Additionally, mechanical properties of the alloy after activation, including performance under high-temperature activation and high-cycle fatigue loadings, were studied.
ENGINEERING STRUCTURES
(2021)
Article
Engineering, Manufacturing
I Ferretto, D. Kim, N. M. Della Ventura, M. Shahverdi, W. Lee, C. Leinenbach
Summary: The iron-based Fe-17Mn-5Si-10Cr-4Ni shape memory alloy (SMA) manufactured by laser powder bed fusion (LPBF) exhibits high strength, elongation, and ductility after annealing, as well as pronounced shape memory effect (SME) and pseudo-elasticity (PE) exceeding those of conventionally fabricated alloys. The texture generated during the LPBF process significantly influences SME and PE, with improved strain recovery observed when the loading direction is parallel to the build direction.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Siyang Wang, Paul Burdett, Edmund Lovell, Rachel Bettles, Neil Wilson, Mary P. Ryan, Finn Giuliani
Summary: La(Fe,Mn,Si)(13) alloys are promising materials for magnetic refrigeration, but their structural integrity during assembly and operation is a challenge that requires understanding of their mechanical properties. In this study, we developed a workflow to quantitatively study the fracture properties of La(Fe,Mn,Si)(13) plates used in magnetic cooling devices. By characterizing the microstructure, examining defects optically, and conducting four-point bending tests, we established a residual strength curve that directly relates observed defects to mechanical strength. The relationship between strength and crack length allows for the prediction of mechanical performance through optical microscopy, which can be used in industry to ensure the mechanical stability of refrigeration devices.
Article
Chemistry, Physical
Fengqi Zhang, Sebastian Smits, Anika Kiecana, Ivan Batashev, Qi Shen, Niels van Dijk, Ekkes Bruck
Summary: The influence of doping with the 5d transition metal W has been studied in the quaternary (Mn,Fe)2(P,Si) based giant magnetocaloric compounds. It is found that W substitution can separately decrease the Curie temperature TC and retain the thermal hysteresis increment Thys at an almost constant level. Low-content W doping conserves the good magnetocaloric effect without an obvious degradation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Na Li, Yun-bin Sun, Rui Sun, Xu Yang, Wei Zhang, Zong-kai Xie, Jia-nan Liu, Yan Li, Yang Li, Zi-zhao Gong, Xiang-qun Zhang, Wei He, Zhao-hua Cheng
Summary: Topological insulators with distinct topological surface states have been widely investigated for spintronics and quantum information devices. This study reveals that the topological surface states can significantly accelerate ultrafast demagnetization and enhance the damping factor of heterostructures. These findings have implications for future topological spintronic devices or quantum information processing.
Article
Physics, Applied
Fu Liu, Jinli Yao, Chenglong Jia, Changjun Jiang
Summary: By changing the direction of applied radio frequency microwave currents, we demonstrate a significant conversion anisotropy of up to 400% in fourfold-symmetric anisotropy Fe films on MgO(100) substrate. The fourfold-symmetric anisotropy stems from large emergent spin-orbit coupling in Fe films with local lattice distortions. Our findings provide a simple route for designing future energy-efficient magnetic devices.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Multidisciplinary
Sheng Jiang, Sunjae Chung, Quang Tuan Le, Ping Kwan Johnny Wong, Wen Zhang, Johan Akerman
Summary: Exchange-spring STNOs are demonstrated to generate high-frequency microwave emission at zero magnetic field and observe magnetic droplet solitons. This extends the design flexibility and functionality of current STNO technology for energy-efficient high-frequency spintronics and neuromorphic applications.
Article
Physics, Applied
Lijun Zhu, Robert A. Buhrman
Summary: After a decade of intensive theoretical and experimental explorations, it remains in dispute whether interfacial spin-orbit coupling at metallic magnetic interfaces can effectively generate a spin current. Utilizing Ti/Fe-Co-B bilayers with unique properties, the study found no significant charge-to-spin conversion at magnetic interfaces, even with stronger ISOC than a typical Pt/ferromagnet interface. Additionally, a minimal orbital Hall effect was observed in 3d Ti.
PHYSICAL REVIEW APPLIED
(2021)
Article
Nanoscience & Nanotechnology
Iduru Shigeta, Shuta Oku, Takahide Kubota, Shojiro Kimura, Takeshi Seki, Bunju Shinozaki, Satoshi Awaji, Koki Takanashi, Masahiko Hiroi
Summary: Superconducting properties of NbN/CMS films were investigated. The upper critical field decreased with increasing CMS thickness, while the superconducting transition temperature had a minimum value at a thickness of around 5 nm. The experimental results suggest that the superconductivity of the NbN layer is affected by the interaction between the NbN and the CMS layers.
Article
Physics, Applied
Atsushi Sugihara, Tomohiro Ichinose, Shingo Tamaru, Tatsuya Yamamoto, Makoto Konoto, Takayuki Nozaki, Shinji Yuasa
Summary: We deposited a 1.1 nm ultrathin CoFeB layer as the storage layer for MgO-based magnetic tunnel junctions in spin-transfer-torque (STT) magnetoresistive random-access memory (MRAM) on phi 300 mm wafers at 100 K, and investigated its effect on the magnetization dynamics of CoFeB. The results show that deposition at cryogenic temperatures is an effective manufacturing process for high-quality magnetic thin films with low magnetic damping, achieved through the improvement in the interfacial quality.
APPLIED PHYSICS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Zhenyu Zhou, William Frost, David C. Lloyd, Takeshi Seki, Takahide Kubota, Rafael Ramos, Eiji Saitoh, Koki Takanashi, Atsufumi Hirohata
Summary: Recent development in neuromorphic computation allows for low power, highly efficient calculations surpassing conventional von Neumann computation. Realistic synaptic operation requires potentiation through reducing electrical resistance of artificial synapses. A recent study demonstrated current-induced crystallisation in a magnetoresistive junction with a ferromagnetic Heusler alloy, which can be extended to epitaxially-grown Heusler alloys for realistic synaptic computation.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Physics, Applied
Tatsuya Yamamoto, Tomohiro Ichinose, Jun Uzuhashi, Takayuki Nozaki, Tadakatsu Ohkubo, Kay Yakushiji, Shingo Tamaru, Shinji Yuasa
Summary: The magnetic and electrical transport properties of magnetic tunnel junctions (MTJs) consisting of a Co75Mn25/Mo/Co20Fe60B20 multilayer were studied. By optimizing the Co75Mn25 layer thickness and annealing temperature, the Co75Mn25/Mo/Co20Fe60B20 multilayer sandwiched between two MgO layers exhibits remarkable perpendicular magnetic anisotropy with a uniaxial magnetic anisotropy constant as large as 0.2 MJ/m3. The current-in-plane tunneling measurement reveals a large tunneling magnetoresistance of over 100% in perpendicularly magnetized MTJs. These experimental results indicate the applicability of Co75Mn25 alloy for magnetic random access memory devices.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Applied
Soki Kobayashi, Hiroki Koizumi, Hideto Yanagihara, Jun Okabayashi, Takahiro Kondo, Takahide Kubota, Koki Takanashi, Yoshiaki Sonobe
Summary: The study investigates the magnetic anisotropy and magnetic interactions at the interface between Fe and NiO(001). The preferential magnetization direction of the ultrathin Fe layer on NiO(001) changed depending on the growth conditions and post-annealing temperature. The lattice constant of NiO(001) layers parallel to the growth direction increased with O2 flow rate, while those parallel to the in-plane direction were locked onto the MgO(001) substrate. Perpendicular magnetization was observed only when the NiO layer was grown with high O2 flow rates. The magnetic anisotropy energies at the interface were temperature-independent, while the coercivity exhibited a significant temperature dependence. The exchange interaction between the ferromagnetic and antiferromagnetic layers was not negligible, despite NiO(001) being a spin-compensated surface.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Applied
Tariq F. Alhuwaymel, Takahide Kubota, Jun-Young Kim, Koki Takanashi, Atsufumi Hirohata
Summary: Researchers have developed a new technique to directly measure the half-metallic bandgap by using circularly polarized infrared light. This technique can provide a simple evaluation of the properties of a half-metallic film.
Article
Physics, Applied
Takumi Yamazaki, Takeshi Seki, Takahide Kubota, Koki Takanashi
Summary: This study reports the effect of epitaxial growth on the spin current transmission of NiO films. Two series of samples, including epitaxial and polycrystalline NiO, were prepared using different deposition conditions. The spin current transmission of NiO was evaluated using thermo-spin effects. Epitaxial NiO exhibited a non-monotonic behavior in the thickness dependence of spin current transmission, revealing the presence of multiple spin transport mechanisms.
APPLIED PHYSICS EXPRESS
(2023)
Article
Physics, Applied
Makoto Kohda, Takeshi Seki, Yasushi Yuminaka, Tetsuya Uemura, Keito Kikuchi, Gian Salis
Summary: This article discusses the differences between waves and particle properties, as well as their applications in data processing and storage. It introduces the information theory of wave-parallel computing and the fundamental properties needed for wave-based information carriers. The potential of electron spin waves and magnons as information carriers for processing and storage is examined. The interconversion among light helicity, electron spin waves, and magnons is also discussed.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
A. Nabialek, O. M. Chumak, P. Aleshkevych, J. Z. Domagala, A. Pacewicz, B. Salski, J. Krupka, T. Seki, K. Takanashi, L. T. Baczewski, H. Szymczak
Summary: In this study, the perpendicular magnetocrystalline anisotropy, magnetoelastic properties, and Gilbert damping factor in Co2Fe0.4Mn0.6Si thin films were found to be dependent on the magnetic layer thickness and could be tuned by the addition of an Ag buffer layer. The tetragonal distortion of the magnetic layer increased with decreasing thickness, and the character of this distortion changed from tensile to compressive in the plane of the film after the application of an additional Ag buffer layer. There was a correlation between the tetragonal distortion and perpendicular magnetocrystalline anisotropy, but the observed magnitude of the tetragonal distortion seems to be too small to fully explain the experimentally found large magnitude of the perpendicular magnetocrystalline anisotropy in most samples.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Multidisciplinary
Takeshi Seki, Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa, Satoshi Iihama, Kentaro Nomura, Atsushi Tsukazaki
Summary: In this paper, the temperature dependence of conversion between charge current and spin current for CSS thin film was investigated. The spin-torque ferromagnetic resonance (ST-FMR) measurement was performed on a CSS/Cu/CoFeB trilayer structure. It was found that both the anisotropic magnetoresistance (AMR) and the giant magnetoresistance (GMR) contribute to the ST-FMR signal below the ferromagnetic phase transition temperature (TC). The results also showed an increase in spin-charge conversion efficiency at T < TC.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Nanoscience & Nanotechnology
Takayuki Nozaki, Tomohiro Ichinose, Jun Uzuhashi, Tatsuya Yamamoto, Makoto Konoto, Kay Yakushiji, Tadakatsu Ohkubo, Shinji Yuasa
Summary: This study investigates the influence of the buffer material and cryogenic temperature deposition process on the voltage-controlled magnetic anisotropy (VCMA) effect in CoFeB layers in MgO-based magnetic tunnel junctions. The use of TaB buffers allows for a flat and less-contaminated CoFeB/MgO interface while cryogenic temperature deposition enhances the efficiency of the VCMA effect and its annealing tolerance. Introduction of interface engineering methods leads to a large VCMA coefficient.
Article
Materials Science, Multidisciplinary
Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa, Jiaxin Zheng, Takeshi Seki, Kentaro Nomura, Liang Du, Quansheng Wu, Atsushi Tsukazaki, Koki Takanashi
Summary: Magnetic Weyl semimetals exhibit chiral Weyl node pairs and large intrinsic anomalous Hall effect. This study demonstrates the potential of Dirac nodes in paramagnetic state for efficient spin current generation at room temperature via the spin Hall effect.
Review
Computer Science, Information Systems
Atsufumi Hirohata, David C. Lloyd, Takahide Kubota, Takeshi Seki, Koki Takanashi, Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, Hiroki Koizumi
Summary: Spintronic devices show promise in replacing nanoelectronic memories and sensors due to their efficiency and scalability. To achieve further miniaturization, new materials development is necessary, such as increasing spin polarization or using antiferromagnets. Recent studies have found interesting properties in antiferromagnetic materials, such as 100% spin-polarized current and topological effects. This review summarizes the recent development of three types of antiferromagnets and discusses their potential for device applications.
