Publications de Mohammad Hamdi

Deterministic switching of antiferromagnetic spin textures by nonlinear magnons

Jean-Philippe Ansermet, Dirk Grundler, Mohammad Hamdi, Mingran Xu

Antiferromagnetic spin textures, compared to their ferromagnetic counterparts, innately possess high stability with respect to external disturbance and high-frequency dynamics compatible with ultrafast information processing. However, deterministic creatio ...

DIN Media GmbH2025

Antiferromagnetic droplet soliton driven by spin current

Mohammad Hamdi

We demonstrate that a spin current flowing through a nanocontact into a uniaxial antiferromagnet with first- and second-order anisotropy can excite a self-localized dynamic magnetic soliton, known as a spin-wave droplet in ferromagnets. The droplet nucleat ...

AIP American Institute of Physics2024

Confined spin waves in magnetochiral nanotubes with axial and circumferential magnetization

Dirk Grundler, Mohammad Hamdi, Andrea Mucchietto, Maria Carmen Giordano

We report experimental studies of spin-wave excitations in individual 22-nm-thick Ni80Fe20 nanotubes with diameters of about 150 nm. We apply Brillouin light-scattering spectroscopy under microwave irradiation, and we resolve sets of discrete resonances in ...

2023

Spin wave dispersion of ultra-low damping hematite ( α−Fe2O3 ) at GHz frequencies

Dirk Grundler, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

Low magnetic damping and high group velocity of spin waves (SWs) or magnons are two crucial parameters for functional magnonic devices. Magnonics research on signal processing and wave-based computation at GHz frequencies focused on the artificial ferrimag ...

2023

Broadband spectroscopy and inelastic light scattering on the canted antiferromagnet hematite for antiferromagnetic magnonics

Mohammad Hamdi

Collective spin excitations propagating in magnetically ordered materials are called spin waves (SWs) or magnons. They are promising for low-power and beyond-CMOS information processing, which do not suffer from the ohmic losses. SWs in ferromagnets (antif ...

EPFL2023

Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies

Dirk Grundler, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

Raw data associated to the manuscript ‘’Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies‘’, Physical Review Materials 7, 054407(2023); doi: 10.1103/PhysRevMaterials.7.054407 Information about file fo ...

Zenodo2023

Realization and Control of Bulk and Surface Modes in 3D Nanomagnonic Networks by Additive Manufacturing of Ferromagnets

Dirk Grundler, Mohammad Hamdi, Mingran Xu, Huixin Guo, Axel Johan Marie Deenen

The high-density integration in information technology fuels the research on functional 3D nanodevices. Particularly ferromagnets promise multifunctional 3D devices for nonvolatile data storage, high-speed data processing, and non-charge-based logic operat ...

Wiley2023

van der Waals Epitaxy of Co10–xZn10–yMnx+y Thin Films: Chemical Composition Engineering and Magnetic Properties

Anna Fontcuberta i Morral, Dirk Grundler, Ping Che, Mohammad Hamdi, Andrea Mucchietto, Jean-Baptiste Leran, Simon Robert Escobar Steinvall, Rajrupa Paul

Topologically protected magnetic skyrmions have raised interest for future spintronics applications. One of the main challenges is the synthesis of room temperature skyrmion-hosting materials that are compatible with thin-film technology. We present an app ...

2021

Magnetoelastic coupling enabled tunability of magnon spin current generation in two-dimensional antiferromagnets

Mohammad Hamdi

We theoretically investigate the magnetoelastic coupling (MEC) and its effect on magnon transport in two-dimensional antiferromagnets with a honeycomb lattice. MEC coefficients along with magnetic exchange parameters and spring constants are computed for m ...

2021

Direct observation of multiband transport in magnonic Penrose quasicrystals via broadband and phase-resolved spectroscopy

Dirk Grundler, Sho Watanabe, Mohammad Hamdi, Vinayak Shantaram Bhat, Korbinian Baumgärtl

Quasicrystals are aperiodically ordered structures with unconventional rotational symmetry. Their peculiar features have been explored in photonics to engineer bandgaps for light waves. Magnons (spin waves) are collective spin excitations in magnetically o ...

2021