"Ultrafast Spin Manipulation in Engineered Magnetic Materials: Paving the Way for Next-Generation Computing"

Presented by:  Dr. Anjan Barman, Senior Professor and Dean (Faculty) from S.N. Bose National Centre for Basic Sciences, India

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. For them to become viable and sustainable technology it is imperative to study excitation, manipulation and detection of spin dynamics in artificially structured magnetic materials. Besides, novel effects such as spin-orbit effects, pure spin current transport, spin textures, hybrid magnonics, voltage-controlled magnetism have made strong influences in a rich variety of phenomena occurring over a wide range of time-scale and length-scale.

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 [1-2]. Investigation of spin Hall effect [3-4] and spin pumping effect [5-6] in ferromagnet(FM)/nonmagnet (NM) or 2D materials systems by a novel all-optical measurement of modulation of damping and the role of spin mixing conductance, interfacial spin transparency, spin-diffusion length and two-magnon scattering will be conferred. The effects of pure spin current on the ultrafast demagnetization process in graphene/FM heterostructure and its electrical control will be discussed [6-7]. Interfacial Dzyaloshinskii-Moriya interaction is cardinal in stabilizing chiral spin textures in FM/NM heterostructures, and we will demonstrate its precise detection and quantification using asymmetric spin-wave dispersion in Brillouin light scattering experiment and probing of its microscopic origin by first principles-calculations [8-9]. Finally, we will discuss an emergent phenomenon in reconfigurable and hybrid magnonics, namely voltage controlled on-demand magnonics [10].

References

1. S. Pan et al. Phys. Rev. B 98, 214436 (2018); 2. A. K. Mondal et al. ACS Nano 18, 16914 (2024); 3. A. Ganguly et al. Appl. Phys. Lett. 105, 112409 (2014); 4. S. Mondal et al., Phys. Rev. B 96, 054414 (2017); 5. S. Panda et al. Sci. Adv. 5, eeav7200 (2019); 6. S. Panda et al., Nanoscale 13, 13709 (2021); 7. D. M. Belinchón, S. Mukhopadhyay et al. Phys. Rev. Lett. 135, 097001 (2025); 8. A. K. Chaurasiya et al. Phys. Rev. B 99, 035402 (2019); 9. S. Pal et al. ACS Nano 19, 23564–23574 (2025); 10. S. Choudhury et al. Sci. Adv. 6, eaba5457 (2020).