This paper provides an extension to the earlier work wherein a comparison between different models that had studied the effects of several parameters scaling on the performance of carbon nano tube field-effect transis...This paper provides an extension to the earlier work wherein a comparison between different models that had studied the effects of several parameters scaling on the performance of carbon nano tube field-effect transistors was presented. The evaluation for the studied models, with regard to the scaling effects, was to determine those which best reflect the very essence of carbon nano-tube technologies. Whereas the models subject this comparison (Fettoy, Roy, Stanford, and Southampton) were affected to varying degrees due to such parametric variations, the Stanford model was shown as still being valid for a wide range of chiralities and diameter sizes; a model that is also applicable for circuit simulations. In this paper, we present a comparative assessment of the various models subject to the study with regard to the effect of incorporating multiple carbon nanotubes in the channel region. We also assess the effect of oxide thickness on transistor performance in terms of the supply voltage threshold effects. Results leveraging our findings in this ongoing research endeavor reveal that many research efforts were not efficient to high degree due to high delay and not valid for circuit simulations.展开更多
Chiral magnetic skyrmions are topological swirling spin textures that hold promise for future information technology. The electrical nucleation and motion of skyrmions have been experimentally demonstrated in the last...Chiral magnetic skyrmions are topological swirling spin textures that hold promise for future information technology. The electrical nucleation and motion of skyrmions have been experimentally demonstrated in the last decade, while electrical detection compatible with semiconductor processes has not been achieved, and this is considered one of the most crucial gaps regarding the use of skyrmions in real applications. Here, we report the direct observation of nanoscale skyrmions in Co Fe B/Mg O-based magnetic tunnel junction devices at room temperature. High-resolution magnetic force microscopy imaging and tunneling magnetoresistance measurements are used to illustrate the electrical detection of skyrmions,which are stabilized under the cooperation of interfacial Dzyaloshinskii–Moriya interaction, perpendicular magnetic anisotropy, and dipolar stray field. This skyrmionic magnetic tunnel junction shows a stable nonlinear multilevel resistance thanks to its topological nature and tunable density of skyrmions under current pulse excitation. These features provide important perspectives for spintronics to realize highdensity memory and neuromorphic computing.展开更多
文摘This paper provides an extension to the earlier work wherein a comparison between different models that had studied the effects of several parameters scaling on the performance of carbon nano tube field-effect transistors was presented. The evaluation for the studied models, with regard to the scaling effects, was to determine those which best reflect the very essence of carbon nano-tube technologies. Whereas the models subject this comparison (Fettoy, Roy, Stanford, and Southampton) were affected to varying degrees due to such parametric variations, the Stanford model was shown as still being valid for a wide range of chiralities and diameter sizes; a model that is also applicable for circuit simulations. In this paper, we present a comparative assessment of the various models subject to the study with regard to the effect of incorporating multiple carbon nanotubes in the channel region. We also assess the effect of oxide thickness on transistor performance in terms of the supply voltage threshold effects. Results leveraging our findings in this ongoing research endeavor reveal that many research efforts were not efficient to high degree due to high delay and not valid for circuit simulations.
基金financial support from the National Key R&D Program of China(2018YFB0407602,and 2020YFA0309300)National Natural Science Foundation of China(61627813,61871008,62001019,12004024,and 51901081)+5 种基金Beijing Natural Science Foundation(4202043)Beijing Nova Program from Beijing Municipal Science and Technology Commission(Z201100006820042)National Natural Science Foundation of China-German Research Foundation(52061135105)Outstanding Research Project of Shen Yuan Honors College,BUAA(230121102)the Science and Technology Program of Guangzhou(202002030052)Joint Research Key Fund for Guangzhou and Shen Zhen(2021B1515120047)。
文摘Chiral magnetic skyrmions are topological swirling spin textures that hold promise for future information technology. The electrical nucleation and motion of skyrmions have been experimentally demonstrated in the last decade, while electrical detection compatible with semiconductor processes has not been achieved, and this is considered one of the most crucial gaps regarding the use of skyrmions in real applications. Here, we report the direct observation of nanoscale skyrmions in Co Fe B/Mg O-based magnetic tunnel junction devices at room temperature. High-resolution magnetic force microscopy imaging and tunneling magnetoresistance measurements are used to illustrate the electrical detection of skyrmions,which are stabilized under the cooperation of interfacial Dzyaloshinskii–Moriya interaction, perpendicular magnetic anisotropy, and dipolar stray field. This skyrmionic magnetic tunnel junction shows a stable nonlinear multilevel resistance thanks to its topological nature and tunable density of skyrmions under current pulse excitation. These features provide important perspectives for spintronics to realize highdensity memory and neuromorphic computing.