Publications by authors named "S Krishnia"
In magnetic systems, angular momentum is carried by spin and orbital degrees of freedom. Nonlocal devices, comprising heavy-metal nanowires on magnetic insulators like yttrium iron garnet (YIG), enable angular momentum transport via magnons. These magnons are polarized by spin accumulation at the interface through the spin Hall effect (SHE) and detected via the inverse SHE (iSHE).
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- Magnetic skyrmions are special magnetic formations behaving like particles and are primarily examined in static conditions, but this study investigates their dynamics in thin films.
- Researchers used advanced imaging techniques to track skyrmion movements in fluid-like ensembles and found that altering the geometry of their channels can change how they flow.
- Unlike typical particles, skyrmions show unique behaviors, such as flow asymmetries and the ability to move against applied forces, highlighting their distinct characteristics compared to other quasiparticle fluids.
Article Synopsis
- Recent experiments demonstrated a significant increase in torques when a thin aluminum layer was added to a cobalt/platinum heterostructure, indicating a possible Rashba-like interaction at the Co/Al interface.
- First-principles calculations revealed that this interaction leads to the emergence of a large helical orbital texture in the cobalt layer, driven by the orbital Rashba effect and the formation of surface states at the interface.
- The study highlights that this orbital texture results in a nonequilibrium orbital accumulation, producing large current-induced torques and providing a theoretical foundation for using orbital transport phenomena in all-metallic magnetic systems with lighter elements.
The last decade has seen significant improvements in our understanding of skyrmions current induced dynamics, along with their room temperature stabilization, however, the impact of local material inhomogeneities still remains an issue that impedes reaching the regime of steady state motion of these spin textures. Here, we study the spin-torque driven motion of skyrmions in synthetic ferrimagnetic multilayers with the aim of achieving high mobility and reduced skyrmion Hall effect. We consider Pt|Co|Tb multilayers of various thicknesses with antiferromagnetic coupling between the Co and Tb magnetization.
View Article and Find Full Text PDFPhysical reservoir computing leverages the dynamical properties of complex physical systems to process information efficiently, significantly reducing training efforts and energy consumption. Magnetic skyrmions, topological spin textures, are promising candidates for reservoir computing systems due to their enhanced stability, non-linear interactions and low-power manipulation. Traditional spin-based reservoir computing has been limited to quasi-static detection or real-world data must be rescaled to the intrinsic timescale of the reservoir.
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