Ultrafast Spin Dynamics in Confined Ferromagnetic systems for Applications in Spintronics and Magnonics

Spintronics and Magnonics are rapidly emerging fields with myriad applications in magnetic storage, memory, logic, sensors, microwave source, data communication and processing as well as wave-based computing [1]. For them to become viable and sustainable technology it is imperative to study excitation, manipulation and detection of spin dynamics in artificially structured ferromagnetic materials. Besides, novel effects such as spin-orbit effects, pure spin current transport, spin textures, hybrid magnonics, voltage controlled magnetic anisotropy have made strong influence in a rich variety of phenomena occurring over a wide range of timescale and lengthscale.

Here, we will discuss ultrafast demagnetization, remagnetization, transient magnetic enhancement (TME), precession, Gilbert damping and spin waves in different ferromagnetic thin films, heterostructures, nanostructures and spin textures. The role of spin-flip scattering and spin/thermal transport in ultrafast demagnetization and TME will be discussed [2-3]. Investigation of spin Hall effect [4-5] and spin pumping effect [6-7] in ferromagnet(FM)/nonmagnet (NM) or 2D materials systems by a novel all-optical measurements of modulation of damping and the role of spin mixing conductance, interfacial spin transparency, spin-diffusion length and two-magnon scattering will be conferred. Interfacial Dzyaloshinskii-Moriya interaction is cardinal in stabilizing chiral spin textures in FM/NM heterostructures, and we will demonstrate its precise detection and quantification in above systems using asymmetric spin-wave dispersion in Brillouin light scattering experiment [8-10].

Hybrid magnonics will play important role in quantum transduction and coherent information processing. Here, we will discuss magnon-magnon coupling in nanomagnets mediated by dynamic dipolar coupling and microwave excitation power [11]. We will further discuss developments in magnon-phonon coupling and formation of tripartite magnon-phonon-magnon bipolaron mediated by surface acoustic waves [12]. Finally, we will discuss some emergent phenomena in reconfigurable magnonics including voltage controlled on-demand magnonics [13] and coherent magnon transfer through three-dimensional magnonic nano-architecture [14].

References

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