Article
Chemistry, Multidisciplinary
Ali Hallal, Jinghua Liang, Fatima Ibrahim, Hongxin Yang, Albert Fert, Mairbek Chshiev
Summary: By comparing the behavior of Dzyaloshinskii-Moriya interaction (DMI) and perpendicular magnetic anisotropy (PMA) at graphene/Co and h-BN/Co interfaces, it is found that the latter shows slightly larger DMI and similar PMA, which leads to the formation of skyrmions under thicker Co layers.
Article
Materials Science, Multidisciplinary
Adam B. Cahaya, Alejandro O. Leon
Summary: This study predicts the existence of anisotropic conduction electron spin density in metals with heavy magnetic impurities, and suggests that this spin density is caused by spin-dependent skew scattering of heavy atoms. The spin density induces the Dzyaloshinskii-Moriya interaction between magnetic moments in metals, providing a flexible control mechanism for anisotropic couplings.
Article
Physics, Multidisciplinary
J. H. Guo, Y. Hou, X. Zhang, Philip W. T. Pong, Y. Zhou
Summary: The skyrmion Hall effect is a critical issue in skyrmion future applications. It can be eliminated by modifying the perpendicular magnetic anisotropy coefficients and spin polarization angles, providing a useful method for the design of skyrmion-based spintronics devices without the skyrmion Hall effect.
Article
Physics, Multidisciplinary
J. H. Guo, J. Xia, X. Zhang, Philip W. T. Pong, Y. Zhou
Summary: A computational study of a ferromagnetic skyrmion-based nanooscillator model with a composite structure was conducted, where the skyrmion dynamics is controlled by modifying perpendicular magnetic anisotropy. The nano-oscillator structure has two concentric circular areas with different anisotropy coefficients, and when the inner area has larger anisotropy than the outer area, a repulsive force is exerted on the skyrmion causing it to move along the edge of the inner circular area.
Article
Chemistry, Multidisciplinary
Fengjun Zhuo, Hang Li, Zhenxiang Cheng, Aurelien Manchon
Summary: A magnonic metamaterial with spatially modulated Dzyaloshinskii-Moriya interaction is proposed and demonstrated through micromagnetic simulations. The magnonic Snell's law is established to describe the behavior of spin waves passing through an interface between two media with different dispersion relations due to different Dzyaloshinskii-Moriya interactions. Based on this law, total internal reflection of spin waves is observed, with the critical angle depending on the sign and strength of Dzyaloshinskii-Moriya interaction. Furthermore, spin-wave beam fiber and spin-wave lens are designed using the artificial magnonic metamaterials. These findings open up new possibilities for spin wave manipulation in magnonics.
Article
Nanoscience & Nanotechnology
Zedong Xu, Qi Liu, Yanjiang Ji, Xiaowen Li, Junxue Li, Junling Wang, Lang Chen
Summary: In this study, the topological spin textures in magnetic insulator films were investigated by detecting the spin-Hall topological Hall effect (SH-THE). It was found that the topological spin textures can be tuned by epitaxial strain. The study also indicated that the Pt/TmIG bilayer configuration can record the topological spin textures at room temperature and low field.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Trae L. Staggers, Liyan Jacob, Shawn D. Pollard
Summary: The discovery of asymmetric domain wall velocities in magnetic alloys and multilayers without a heavy metal underlayer has led to claims of a large Dzyaloshinskii-Moriya interaction (DMI) driven by compositional non-uniformities. However, these non-uniformities also lead to vertically non-uniform magnetic properties which can affect the dynamic properties of domain walls. In this study, micromagnetic simulations are used to demonstrate that vertical modulation of saturation magnetization can result in asymmetric domain wall velocities for field and current driven motion, resembling the presence of DMI. The magnitude of effective symmetry breaking field resulting from non-uniformity is comparable to DMI, but this effect is suppressed for SOT driven domain dynamics. Careful evaluation of DMI is required in non-uniform systems.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Satoru Hayami, Ryota Yambe
Summary: This article investigates the possibility of a skyrmion crystal in noncentrosymmetric magnets by simulating annealing on a triangular lattice. The results show that the instability and stabilization mechanisms of SkX vary with different magnetic field directions and types of DM interactions.
Article
Physics, Applied
Esita Pandey, Brindaban Ojha, Subhankar Bedanta
Summary: The strength of the interfacial Dzyaloshinskii-Moriya interaction (iDMI) and the dynamics of domain walls (DWs) were investigated in a Pd/Co/C60/Pd system. The iDMI was found to increase from -0.07 to -0.46 mJ/m2 with increasing C60 thickness, transforming an achiral Bloch wall into a chiral Neel wall. This is significant for the use of carbon-based materials in chiral-DW-based device applications.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Multidisciplinary
Jingdi Lu, Liang Si, Qinghua Zhang, Chengfeng Tian, Xin Liu, Chuangye Song, Shouzhe Dong, Jie Wang, Sheng Cheng, Lili Qu, Kexuan Zhang, Youguo Shi, Houbing Huang, Tao Zhu, Wenbo Mi, Zhicheng Zhong, Lin Gu, Karsten Held, Lingfei Wang, Jinxing Zhang
Summary: This study demonstrates the successful construction of a sharp interface with significant Dzyaloshinskii-Moriya interaction in spin-orbit-coupled transition-metal oxides through atomic design of defective interfaces. The interfacial inversion-symmetry breaking allows for reversible manipulation of the topological spin texture, leading to deterministic ON and OFF switching of the topological Hall signal. These defect-engineered topological spin textures may hold promise for future skyrmion-based memristor and synaptic devices.
ADVANCED MATERIALS
(2021)
Article
Physics, Multidisciplinary
Dongxing Yu, Yonglong Ga, Jinghua Liang, Chenglong Jia, Hongxin Yang
Summary: Magnetization switching, an essential operation in spintronic devices, is usually achieved by spin-transfer torque or spin-orbit torque. However, these techniques require current and can cause Joule heating. This study introduces an alternative mechanism called Dzyaloshinskii-Moriya interaction torque, which allows for magnetization switching controlled by voltage pulses, offering potential for magnetic-field-free and current-free spintronic devices and neuromorphic computing.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Jiawei Jiang, Zhiwen Wang, Jinghua Liang, Qirui Cui, Wenbo Mi, Hongxin Yang
Summary: This study investigates the interfacial Dzyaloshinskii-Moriya interaction (DMI) and magnetic anisotropy in Co/Dia interfaces using first-principles calculations. It is found that the DMI strength and chirality vary on different doped diamond substrates, with a significant clockwise DMI observed at the Co/diamond interface. Additionally, diverse perpendicular magnetic anisotropy is observed at different interfaces, demonstrating potential for tailoring the properties of ferromagnetic films for modulating topological magnetic textures.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Wenqing He, Caihua Wan, Cuixiu Zheng, Yizhan Wang, Xiao Wang, Tianyi Ma, Yuqiang Wang, Chenyang Guo, Xuming Luo, Maksim E. Stebliy, Guoqiang Yu, Yaowen Liu, Alexey V. Ognev, Alexander S. Samardak, Xiufeng Han
Summary: This study observes an intrinsic interlayer chiral interaction effect in a Pt/Co multilayer film and its synthetic antiferromagnetic counterpart with perpendicular magnetic anisotropy. By applying a current parallel to the eigenvector of the interlayer interaction, the perpendicular magnetization of both structures can be switched without a magnetic field, providing a new possibility for practical perpendicular SOT-MRAM and other SOT devices.
Article
Materials Science, Multidisciplinary
Yaqin Guo, Jingyan Zhang, Qirui Cui, Ruoyang Liu, Yonglong Ga, Xiaozhi Zhan, Haochang Lyu, Chaoqun Hu, Jialiang Li, Jianjin Zhou, Hongxiang Wei, Tao Zhu, Hongxin Yang, Shouguo Wang
Summary: Researchers observed the evidence of interlayer Dzyaloshiniskii-Moriya interaction (DMI) at room temperature, which can be used to manipulate magnetic chirality effectively. Noncollinear magnetic states were characterized and quantified using polarized neutron reflectometry (PNR). The findings are important for the interface design of spintronic devices.
Article
Chemistry, Multidisciplinary
Fabian Kammerbauer, Won-Young Choi, Frank Freimuth, Kyujoon Lee, Robert Froemter, Dong-Soo Han, Reinoud Lavrijsen, Henk J. M. Swagten, Yuriy Mokrousov, Mathias Klaeui
Summary: The recently discovered interlayer Dzyaloshinskii-Moriya interaction (IL-DMI) in multilayers with perpendicular magnetic anisotropy can stabilize intriguing spin textures such as Hopfions. To control the IL-DMI, the influence of an electric current on a synthetic antiferromagnet with growth-induced IL-DMI was investigated. The study revealed that the azimuthal dependence of IL-DMI shifts with increasing current, suggesting the presence of an additional current-induced term that linearly increases the IL-DMI in the direction of current flow, opening the possibility of easily manipulating 3D spin textures by currents.
Article
Physics, Multidisciplinary
Linlin Li, Jia Luo, Jing Xia, Yan Zhou, Xiaoxi Liu, Guoping Zhao
Summary: Skyrmions in synthetic antiferromagnetic (SAF) systems have recently gained attention for their stability, mobility, and skyrmion Hall effect. They are promising for ultra-low energy and ultra-high density magnetic storage and computing devices. In this study, we theoretically investigate the motion of a skyrmion in an SAF bilayer racetrack and propose a logic gate that can realize different logic functions. Our work considers various effects and may contribute to utilizing SAF skyrmions as versatile information carriers for future energy-efficient logic gates.
Article
Nanoscience & Nanotechnology
Zichao Li, Ye Yuan, Rene Huebner, Lars Rebohle, Yan Zhou, Manfred Helm, Kornelius Nielsch, Slawomir Prucnal, Shengqiang Zhou
Summary: In this study, pure B20-CoSi thin films were successfully grown using millisecond-range flash-lamp annealing, and the phenomena of charge density wave and chiral anomaly were observed. This work presents a promising method for preparing thin films of other binary B20 transition-metal silicides.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Teng Xu, Yuxuan Zhang, Zidong Wang, Hao Bai, Chengkun Song, Jiahao Liu, Yan Zhou, Soong-Geun Je, Alpha T. N'Diaye, Mi-Young Im, Rong Yu, Zhen Chen, Wanjun Jiang
Summary: We propose a viable approach to design ferrimagnetic skyrmions with desired size and density by tuning the magnetic properties of Fe1-xTbx. This method could be useful for enabling high-density ferrimagnetic skyrmionics.
Article
Optics
Yifan Shao, Shuhan Guo, Rui Chen, Yongdi Dang, Yi Zhou, Yubo Wang, Junjie Zhan, Jiaqi Yu, Bing-Feng Ju, Yungui Ma
Summary: The in-built color filters in conventional image sensors cause significant out-of-band energy loss, leading to degradation in signal-to-noise ratio and dynamic range. This study presents a pixelated spectral router using a 2D Si3N4 Mie-type metagrating, which efficiently separates near-infrared and visible light to different pixels. Compared to traditional filter designs, this router achieves approximately 42% and 30% signal enhancement for the near-infrared and visible bands, respectively.
LASER & PHOTONICS REVIEWS
(2023)
Article
Physics, Multidisciplinary
Jing Xia, Xichao Zhang, Xiaoxi Liu, Yan Zhou, Motohiko Ezawa
Summary: We propose a skyrmion-based universal quantum computer that utilizes the helicity degree of freedom in frustrated magnets. It is shown that the quantum computation can be achieved based on nanoscale skyrmions in a magnetic bilayer system. Single-qubit gates are realized by controlling the electric field and spin current, while the two-qubit gate is achieved through Ising-type exchange coupling. The advantage of this mechanism is the elimination of the need for an external magnetic field. Our results may pave the way for universal quantum computation based on nanoscale topological spin textures.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yuelei Zhao, Sheng Yang, Kai Wu, Shuang Li, Yang Gao, Hongyuan Hao, Xichao Zhang, Shouguo Wang, Qingfang Liu, Senfu Zhang, Zhiqin Chu, Johan Akerman, Yan Zhou
Summary: Synthetic antiferromagnetic (SAF) skyrmions, with high mobility and no skyrmion Hall effect, are emerging as novel information carriers. However, distinguishing SAF skyrmions from ferromagnetic ones using imaging techniques remains challenging. In this study, a universal identification method is proposed, and the motion of SAF skyrmions with suppressed skyrmion Hall effect is investigated. These findings will accelerate the realization of practical applications based on SAF skyrmions.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Xiuzhen Yu, Naoya Kanazawa, Xichao Zhang, Yoshio Takahashi, Konstantin V. Iakoubovskii, Kiyomi Nakajima, Toshiaki Tanigaki, Masahito Mochizuki, Yoshinori Tokura
Summary: This study reports the on-demand creation of multiple topological states in a helimagnet Fe0.5Co0.5Ge, including merons, antimerons, bimerons, and skyrmions, and demonstrates the transformations among these states through the application of magnetic fields and electric currents. These findings offer new insights into the manipulation of noncollinear spin textures and have potential applications in various fields.
ADVANCED MATERIALS
(2023)
Article
Optics
Yi Zhou, Junjie Zhan, Ziyang Xu, Yifan Shao, Yubo Wang, Yongdi Dang, Sen Zhang, Yungui Ma
Summary: This paper experimentally demonstrates an analog spatiotemporal differentiator in microwaves based on an asymmetrical metasurface. By tailoring the unidirectional excitation of spoof surface plasmon polaritons, the structure achieves the spatiotemporal transfer function required by an ideal first-order differentiator in both spatial and temporal domains. The experimental results verify the spatial edge detection and temporal differentiation functions of the device, and estimate the resolution limits of the spatial and temporal edge detection. Moreover, it is found that the pulse input after passing the spatiotemporal differentiator can carry a transverse orbital angular momentum (OAM) with a fractal topology charge.
LASER & PHOTONICS REVIEWS
(2023)
Article
Materials Science, Multidisciplinary
Yi Zhou, Junjie Zhan, Yifan Shao, Yubo Wang, Yongdi Dang, Sen Zhang, Hugo E. E. Hernandez-Figueroa, Yungui Ma
Summary: This study demonstrates a reconfigurable spatiotemporal optical signal processor using the phase-change material vanadium dioxide (VO2) to expand the processing bandwidth and enrich the operation functions. By controlling the operation temperature, a meta-device is designed that can switch between a first-order differentiator and a reflector in the spatiotemporal domain. The approach enables high-accuracy spatial and temporal signal processing, and holds great potential in applications such as remote sensing and fast imaging processing.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Physics, Applied
Yuxuan Li, Yongdi Dang, Sen Zhang, Xinran Li, Yi Jin, Philippe Ben-Abdallah, Jianbin Xu, Yungui Ma
Summary: Developing thermal analogues of a field-effect transistor could lead to low-power communication technology using heat instead of electricity. Experimental demonstration of a thermal transistor effect using a noncontact system shows that a tiny change in temperature can significantly modify heat flux.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Lan Bo, Rongzhi Zhao, Chenglong Hu, Xichao Zhang, Xuefeng Zhang, Masahito Mochizuki
Summary: In this study, a method for creating skyrmion bags in thin-film nanodisks is proposed, involving three steps: enlarging the size of the outer skyrmion using a vertical magnetic field, nucleating inner skyrmions at an off-center area through local current injection, and reconstructing the system through multiple interskyrmion potentials. As a result, skyrmion bags with a maximum topological charge of 40 can be created. Simulated Lorentz transmission electron microscopy images are provided to facilitate experimental demonstration. This research is expected to inspire relevant experiments in magnetic films and pave the way for potential spintronic applications based on skyrmion bags.
Article
Materials Science, Multidisciplinary
Shuang Li, Motohiko Ezawa, Yan Zhou
Summary: Nucleation and dynamics of isolated antiferromagnetic (AFM) antiskyrmions and antiskyrmioniums induced by current are reported. It is demonstrated that AFM antiskyrmions and antiskyrmioniums can be stabilized and manipulated by spin transfer torques and spin-orbit torques. The driving velocity of AFM antiskyrmions and antiskyrmioniums can reach up to 6 km/s without the skyrmion Hall effect.
Article
Materials Science, Multidisciplinary
Laichuan Shen, Yan Zhou, Ka Shen
Summary: We propose a multifunction logic device based on current-driven skyrmion motion, utilizing spatially modulated Dzyaloshinskii-Moriya interaction to create a potential barrier for the skyrmion. Through micromagnetic simulations, we demonstrate three stable stages of the skyrmion location under different magnitudes of driving current, allowing for the implementation of all necessary logic gates for computing applications. Our proposal presents a feasible scheme to design skyrmion-based programmable logic devices.
Article
Materials Science, Multidisciplinary
Sen Li, Qinyun Li, Jiancheng Liu, Nian Ran, Ping Lai, Laichuan Shen, Jing Xia, Linhua Xie, Yan Zhou, Guoping Zhao
Summary: In this study, a variational method is used to investigate rich topological spin textures in magnetic nanodisks, including skyrmions and skyrmionlike objects. The existence of these spin textures is theoretically studied in single-phase nanodisks and nanodisks with a core-shell structure. The phase diagrams of possible spin states are obtained for various Dzyaloshinskii-Moriya interaction (DMI) constants and disk diameters. The results suggest that skyrmions can be spontaneously generated in a core-shell nanodisk. The transitions of spin textures induced by spin currents in the nanodisk are also studied. This paper provides guidelines for the experimental realization of different topological spin textures in nanodisks with specific DMIs. The simple two-dimensional analytical method used in this paper can be applied to study the magnetic phase diagrams of thin films with interface-induced DMIs.
