Magnetic skyrmions are topological quasiparticles with nanoscale size and high mobility,which have potential applications in information storage and spintronic devices.The manipulation of skyrmion’s dynamics in the t...Magnetic skyrmions are topological quasiparticles with nanoscale size and high mobility,which have potential applications in information storage and spintronic devices.The manipulation of skyrmion’s dynamics in the track is an important topic due to the skyrmion Hall effect,which can deviate the skyrmions from the preferred direction.We propose a new model based on the ferromagnetic skyrmion,where the skyrmion velocity can be well controlled by adjusting the direction of the current.Using this design,we can avoid the annihilation of the skyrmion induced by the skyrmion Hall effect,which is confirmed by our micromagnetic simulation based on Mumax^(3).In the meantime,we increase the average velocity of the skyrmion by varying the intrinsic material parameters in the track,where the simulations agree well with our analytical results based on the Thiele equation.Finally,we give a phase diagram of the output of the skyrmion in the T-type track,which provides some practical ways for design of logic gates by manipulating crystalline anisotropy through the electrical control.展开更多
Skyrmions in synthetic antiferromagnetic(SAF) systems have attracted much attention in recent years due to their superior stability, high-speed mobility, and completely compensated skyrmion Hall effect. They are promi...Skyrmions in synthetic antiferromagnetic(SAF) systems have attracted much attention in recent years due to their superior stability, high-speed mobility, and completely compensated skyrmion Hall effect. They are promising building blocks for the next generation of magnetic storage and computing devices with ultra-low energy and ultra-high density.Here, we theoretically investigate the motion of a skyrmion in an SAF bilayer racetrack and find the velocity of a skyrmion can be controlled jointly by the edge effect and the driving force induced by the spin current. Furthermore, we propose a logic gate that can realize different logic functions of logic AND, OR, NOT, NAND, NOR, and XOR gates. Several effects including the spin–orbit torque, the skyrmion Hall effect, skyrmion–skyrmion repulsion, and skyrmion–edge interaction are considered in this design. Our work may provide a way to utilize the SAF skyrmion as a versatile information carrier for future energy-efficient logic gates.展开更多
Lanthanide-based single-molecule magnets exhibit broad magnetic hysteresis,which manifests as slow magnetic relaxation in strong magnetic fields.However,the origin of the nontrivial hysteresis behaviors remains debate...Lanthanide-based single-molecule magnets exhibit broad magnetic hysteresis,which manifests as slow magnetic relaxation in strong magnetic fields.However,the origin of the nontrivial hysteresis behaviors remains debated.Here,we propose two influential mechanisms:activation of optical-phonon-mediated direct transitions within the ground-state doublet and the resonant Raman process.These discoveries,coupled with the g-factor anisotropy,account for the observed hysteresis behaviors in the regimes of fast magnetic relaxation.Our findings complement the recognized mechanisms used to interpret the magnetic hysteresis of single-molecule magnets.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51771127,52171188,52111530143,11974298,12374123,and 12241403)the Central Government Funds of Guiding Local Scientific and Technological Development of Sichuan Province(Grant No.2021ZYD0025)+3 种基金the Shenzhen Fundamental Research Fund(Grant No.JCYJ20210324120213037)Shenzhen Peacock Group Plan(Grant No.KQTD20180413181702403)the KeyArea Research&Development Program of Guangdong Province(Grant No.2021B0101300003)the Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2022A1515110863 and 2023A1515010837)。
文摘Magnetic skyrmions are topological quasiparticles with nanoscale size and high mobility,which have potential applications in information storage and spintronic devices.The manipulation of skyrmion’s dynamics in the track is an important topic due to the skyrmion Hall effect,which can deviate the skyrmions from the preferred direction.We propose a new model based on the ferromagnetic skyrmion,where the skyrmion velocity can be well controlled by adjusting the direction of the current.Using this design,we can avoid the annihilation of the skyrmion induced by the skyrmion Hall effect,which is confirmed by our micromagnetic simulation based on Mumax^(3).In the meantime,we increase the average velocity of the skyrmion by varying the intrinsic material parameters in the track,where the simulations agree well with our analytical results based on the Thiele equation.Finally,we give a phase diagram of the output of the skyrmion in the T-type track,which provides some practical ways for design of logic gates by manipulating crystalline anisotropy through the electrical control.
基金support from the National Natural Science Foundation of China (Grant Nos.51771127,52171188,and 52111530143)the Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province,China (Grant No.2021ZYD0025)+7 种基金supported by JSPS KAKENHI (Grant No.JP22F22061)support from Guangdong Basic and Applied Basic Research Foundation (Grant No.2021B1515120047)Guangdong Special Support Project (Grant No.2019BT02X030)Shenzhen Fundamental Research Fund (Grant No.JCYJ20210324120213037)Shenzhen Peacock Group Plan (No.KQTD20180413181702403)Pearl River Recruitment Program of Talents (Grant No.2017GC010293)the National Natural Science Foundation of China (Grant Nos.11974298 and 61961136006)support from the Grantsin-Aid Scientific Research from JSPS KAKENHI (Grant Nos.JP20F20363,JP21H01364,and JP21K18872)。
文摘Skyrmions in synthetic antiferromagnetic(SAF) systems have attracted much attention in recent years due to their superior stability, high-speed mobility, and completely compensated skyrmion Hall effect. They are promising building blocks for the next generation of magnetic storage and computing devices with ultra-low energy and ultra-high density.Here, we theoretically investigate the motion of a skyrmion in an SAF bilayer racetrack and find the velocity of a skyrmion can be controlled jointly by the edge effect and the driving force induced by the spin current. Furthermore, we propose a logic gate that can realize different logic functions of logic AND, OR, NOT, NAND, NOR, and XOR gates. Several effects including the spin–orbit torque, the skyrmion Hall effect, skyrmion–skyrmion repulsion, and skyrmion–edge interaction are considered in this design. Our work may provide a way to utilize the SAF skyrmion as a versatile information carrier for future energy-efficient logic gates.
基金the support from the Sichuan Normal Universitysupport from the National Natural Science Foundation of China(Grant No.22375157)+1 种基金support from the National Natural Science Foundation of China(Grant Nos.12474122,52171188,51771127,and 52111530143)the Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province(Grant No.2021ZYD0025)。
文摘Lanthanide-based single-molecule magnets exhibit broad magnetic hysteresis,which manifests as slow magnetic relaxation in strong magnetic fields.However,the origin of the nontrivial hysteresis behaviors remains debated.Here,we propose two influential mechanisms:activation of optical-phonon-mediated direct transitions within the ground-state doublet and the resonant Raman process.These discoveries,coupled with the g-factor anisotropy,account for the observed hysteresis behaviors in the regimes of fast magnetic relaxation.Our findings complement the recognized mechanisms used to interpret the magnetic hysteresis of single-molecule magnets.
