Magnetic droplets,a class of highly nonlinear magnetodynamic solitons,can be nucleated and stabilized in nanocontact spintorque nano-oscillators.Here we experimentally demonstrate magnetic droplets in magnetic tunnel ...Magnetic droplets,a class of highly nonlinear magnetodynamic solitons,can be nucleated and stabilized in nanocontact spintorque nano-oscillators.Here we experimentally demonstrate magnetic droplets in magnetic tunnel junctions(MTJs).The droplet nucleation is accompanied by power enhancement compared with its ferromagnetic resonance modes.The nucleation and stabilization of droplets are ascribed to the double-Co Fe B free-layer structure in the all-perpendicular MTJ,which provides a low Zhang-Li torque and a high pinning field.Our results enable better electrical sensitivity in fundamental studies of droplets and show that the droplets can be utilized in MTJ-based applications and materials science.展开更多
Magnetic force microscopy(MFM)is a powerful technique for studying magnetic microstructures and nanostructures that relies on force detection by a cantilever with a magnetic tip.The detected magnetic tip interactions ...Magnetic force microscopy(MFM)is a powerful technique for studying magnetic microstructures and nanostructures that relies on force detection by a cantilever with a magnetic tip.The detected magnetic tip interactions are used to reconstruct the magnetic structure of the sample surface.Here,we demonstrate a new method using MFM for probing the spatial profle of an operational nanoscale spintronic device,the spin Hall nano-osillator(SHNO),which generates high-intensity spin wave auto-osillations enabling novel microwave applications in magnonics and neuromorphic computing.We developed an MFM system by adding a microwave probe station to allow electrical and microwave characterization up to 40 GHz during the MFM process.SHNOs-based on NiFe/Pt bilayers with a specific design compatible with the developed system-were fabricated and scanned using a Co magnetic force microscopy tip with 10 nm spatial MFM resolution,while a DC current sufficient to induce auto-oscillation flowed.Our results show that this developed method provides a promising path for the characterization and nanoscale magnetic field imaging of operational nano-osilators.展开更多
基金supported by the Beijing Municipal Science and Technology Project(Grant No.Z201100004220002)the National Natural Science Foundation of China(Grant Nos.61627813,61904009)the China Postdoctoral Science Foundation Funded Project(Grant No.2018M641151)。
文摘Magnetic droplets,a class of highly nonlinear magnetodynamic solitons,can be nucleated and stabilized in nanocontact spintorque nano-oscillators.Here we experimentally demonstrate magnetic droplets in magnetic tunnel junctions(MTJs).The droplet nucleation is accompanied by power enhancement compared with its ferromagnetic resonance modes.The nucleation and stabilization of droplets are ascribed to the double-Co Fe B free-layer structure in the all-perpendicular MTJ,which provides a low Zhang-Li torque and a high pinning field.Our results enable better electrical sensitivity in fundamental studies of droplets and show that the droplets can be utilized in MTJ-based applications and materials science.
基金supported by the European Commision FP7-ICT-2011-contract No.317950"MOSAIC"and the European Research Council(ERC)under the European Community's Seventh Framework Programme(FP/2007-2013)/ERC Grant.No.307144"MUSTANG"Support from the Swedish Research Council(VR),the Swedish Foundation for Strategic Research(SSF),the Goran Gustafsson Foundation,and the Knut and Alice Wallenberg Foundation is also gratefullyacknowledged。
文摘Magnetic force microscopy(MFM)is a powerful technique for studying magnetic microstructures and nanostructures that relies on force detection by a cantilever with a magnetic tip.The detected magnetic tip interactions are used to reconstruct the magnetic structure of the sample surface.Here,we demonstrate a new method using MFM for probing the spatial profle of an operational nanoscale spintronic device,the spin Hall nano-osillator(SHNO),which generates high-intensity spin wave auto-osillations enabling novel microwave applications in magnonics and neuromorphic computing.We developed an MFM system by adding a microwave probe station to allow electrical and microwave characterization up to 40 GHz during the MFM process.SHNOs-based on NiFe/Pt bilayers with a specific design compatible with the developed system-were fabricated and scanned using a Co magnetic force microscopy tip with 10 nm spatial MFM resolution,while a DC current sufficient to induce auto-oscillation flowed.Our results show that this developed method provides a promising path for the characterization and nanoscale magnetic field imaging of operational nano-osilators.
