Spin transfer torque in magnetic structure occurs when the transverse component of the spin current that flows from the nonmagnetic medium to ferromagnetic medium is absorbed by the interface. In this paper, consideri...Spin transfer torque in magnetic structure occurs when the transverse component of the spin current that flows from the nonmagnetic medium to ferromagnetic medium is absorbed by the interface. In this paper, considering the Rashba effect on the semiconductor region, we discuss the spin transfer torque in semiconductor/ferromagnetic structure and obtain the components of spin-current density for two models：（i） single electron and（ii） the distribution of electrons. We show that no matter whether the difference in Fermi surface between semiconductor and Fermi spheres for the up and down spins in ferromagnetic increases, the transmission probability decreases. The obtained results for the values used in this article illustrate that Rashba effect increases the difference in Fermi sphere between semiconductor and Fermi sphere for the up and down spins in ferromagnetic. The results also show that the Rashba effect, brings an additional contribution to the components of spin transfer torque, which does not exist in the absence of the Rashba interaction. Moreover, the Rashba term has also different effects on the transverse components of the spin torque transfer.展开更多
Exchange bias(EB)in ferromagnetic/antiferromagnetic materials is a novel idea for high-density spintronic devices.Van der Waals(vdW)heterostructures offer a promising solution,enabling a“Lego”like assembly without i...Exchange bias(EB)in ferromagnetic/antiferromagnetic materials is a novel idea for high-density spintronic devices.Van der Waals(vdW)heterostructures offer a promising solution,enabling a“Lego”like assembly without interface or adding dopants,opposite to traditional heterostructures.However,in typical vdW heterostructures,the EB effect exists at low temperatures and only one polarity.This work addresses these challenges by using Fe_(3)GaTe_(2)/NiPS_(3) heterostructures whose EB can survive at higher temperatures and polarities flip.The exchange bias(EB)of the device persists up to 150 K and can have its polarity reversed by altering the stacking direction during fabrication.Simultaneously,an anomalous Hall effect(A_(HE))with a coercive field of approximately 0.9 T is observed at 5 K and remains detectable up to 300 K.The device further shows the spin-orbit torque(SOT)-induced magnetization switching up to room temperature.Under low field-cooling conditions(e.g.,≥2 mT),we observe an EB field(HEB)up to 1 mT,which reached 110 mT at 1.5 T.HEB becomes zero above 150 K,showing a non-discernible EB effect,whereas the A_(HE) persists up to room temperature.Similarly,in the Fe_(3)GaTe_(2)/NiPS_(3) and NiPS_(3)/Fe_(3)GaTe_(2),different stacking layers at the interface induce the net magnetic effect and flip the magnetization direction due to magnetic domains at the Fe_(3)GaTe_(2) layer.The results show that strong interlayer coupling within these layers generates significant A_(HE) and high HEB with blocking temperatures up to 150 K,making it suitable for the new 2D spintronic device applications.展开更多
文摘Spin transfer torque in magnetic structure occurs when the transverse component of the spin current that flows from the nonmagnetic medium to ferromagnetic medium is absorbed by the interface. In this paper, considering the Rashba effect on the semiconductor region, we discuss the spin transfer torque in semiconductor/ferromagnetic structure and obtain the components of spin-current density for two models：（i） single electron and（ii） the distribution of electrons. We show that no matter whether the difference in Fermi surface between semiconductor and Fermi spheres for the up and down spins in ferromagnetic increases, the transmission probability decreases. The obtained results for the values used in this article illustrate that Rashba effect increases the difference in Fermi sphere between semiconductor and Fermi sphere for the up and down spins in ferromagnetic. The results also show that the Rashba effect, brings an additional contribution to the components of spin transfer torque, which does not exist in the absence of the Rashba interaction. Moreover, the Rashba term has also different effects on the transverse components of the spin torque transfer.
基金National Natural Science Foundation of China,Grant/Award Numbers:5221101553,T2394475Key R&D Projects in Anhui Province,Grant/Award Number:2022i01020012+8 种基金Natural Science Foundation of Hefei,Grant/Award Number:2022039Excellent Research and Innovation Team Project of Anhui Province,Grant/Award Number:2022AH010001Beijing Natural Science Foundation,Grant/Award Number:4232070International Mobility Project,Grant/Award Number:B16001Gordon and Betty Moore Foundation,Grant/Award Number:GBMF9461US DOE,Grant/Award Number:DOE/BES DE-FG-02-05ER46200Deanship of Research and Graduate Studies at King Khalid University,Grant/Award Number:RGP-2/712/46National Science and Technology Major Project,Grant/Award Number:2025ZD0613804Hefei Zhongke Kele New Materials Co.Ltd.,Grant/Award Number:2024340104003776。
文摘Exchange bias(EB)in ferromagnetic/antiferromagnetic materials is a novel idea for high-density spintronic devices.Van der Waals(vdW)heterostructures offer a promising solution,enabling a“Lego”like assembly without interface or adding dopants,opposite to traditional heterostructures.However,in typical vdW heterostructures,the EB effect exists at low temperatures and only one polarity.This work addresses these challenges by using Fe_(3)GaTe_(2)/NiPS_(3) heterostructures whose EB can survive at higher temperatures and polarities flip.The exchange bias(EB)of the device persists up to 150 K and can have its polarity reversed by altering the stacking direction during fabrication.Simultaneously,an anomalous Hall effect(A_(HE))with a coercive field of approximately 0.9 T is observed at 5 K and remains detectable up to 300 K.The device further shows the spin-orbit torque(SOT)-induced magnetization switching up to room temperature.Under low field-cooling conditions(e.g.,≥2 mT),we observe an EB field(HEB)up to 1 mT,which reached 110 mT at 1.5 T.HEB becomes zero above 150 K,showing a non-discernible EB effect,whereas the A_(HE) persists up to room temperature.Similarly,in the Fe_(3)GaTe_(2)/NiPS_(3) and NiPS_(3)/Fe_(3)GaTe_(2),different stacking layers at the interface induce the net magnetic effect and flip the magnetization direction due to magnetic domains at the Fe_(3)GaTe_(2) layer.The results show that strong interlayer coupling within these layers generates significant A_(HE) and high HEB with blocking temperatures up to 150 K,making it suitable for the new 2D spintronic device applications.
