Sucheta Mondal

All-optical detection of the spin Hall angle in W/CoFeB/SiO2 heterostructures with varying thickness of the tungsten layer

The development of advanced spintronics devices hinges on the efficient generation and utilization of pure spin current. In materials with large spin-orbit coupling, the spin Hall effect may convert charge current to pure spin current, and a large conversion efficiency, which is quantified by spin Hall angle (SHA), is desirable for the realization of miniaturized and energy-efficient spintronic devices. Here, we report a giant SHA in beta-tungsten (\ensuremath{\beta}-W) thin films in

Enhanced Amplification and Fan-Out Operation in an All-Magnetic Transistor

\mathrm{Sub}\text{/}\mathrm{W}(t)\text{/}\mathrm{C}{\mathrm{o}}_{20}\mathrm{F}{\mathrm{e}}_{60}{\mathrm{B}}_{20}(3\phantom{\rule{0.16em}{0ex}}\mathrm{nm})\text{/}\mathrm{Si}{\mathrm{O}}_{2}(2\phantom{\rule{0.16em}{0ex}}\mathrm{nm})

All optical detection of picosecond spin-wave dynamics in 2D annular antidot lattice

heterostructures with variable W thickness. We employed an all-optical time-resolved magneto-optical Kerr effect microscope for an unambiguous determination of SHA using the principle of modulation of Gilbert damping of the adjacent ferromagnetic layer by the spin-orbit torque from the W layer. A nonmonotonic variation of SHA with W layer thickness (

Field-controlled ultrafast magnetization dynamics in two-dimensional nanoscale ferromagnetic antidot arrays

t

Transition from strongly collective to completely isolated ultrafast magnetization dynamics in two-dimensional hexagonal arrays of nanodots with varying inter-dot separation

) is observed with a maximum of about 0.4 at about

Influence of thickness-dependent structural evolution on ultrafast magnetization dynamics in C o 2 F e 0.4 M n 0.6 Si Heusler alloy thin films

t=3\phantom{\rule{0.16em}{0ex}}\mathrm{nm}

Investigation of magnetization dynamics in 2D Ni80Fe20 diatomic nanodot arrays

, followed by a sudden reduction to a very low value at

Ultrafast magnetization dynamics in a nanoscale three-dimensional cobalt tetrapod structure

t=6\phantom{\rule{0.16em}{0ex}}\mathrm{nm}

Influence of anisotropic dipolar interaction on the spin dynamics of Ni80Fe20 nanodot arrays arranged in honeycomb and octagonal lattices

. This variation of SHA with W thickness correlates well with the thickness-dependent structural phase transition and resistivity variation of W above the spin-diffusion length of W, while below this length the interfacial electronic effect at W/CoFeB influences the estimation of SHA.

Ultrafast magnetization dynamics in nanoscale two-dimensional Permalloy annular antidot lattices

Development of all-magnetic transistor with favorable properties is an important step towards a new paradigm of all-magnetic computation. Recently, we showed such possibility in a Magnetic Vortex Transistor (MVT). Here, we demonstrate enhanced amplification in MVT achieved by introducing geometrical asymmetry in a three vortex sequence. The resulting asymmetry in core to core distance in the three vortex sequence led to enhanced amplification of the MVT output. A cascade of antivortices travelling in different trajectories including a nearly elliptical trajectory through the dynamic stray field is found to be responsible for this amplification. This asymmetric vortex transistor is further used for a successful fan-out operation, which gives large and nearly equal gains in two output branches. This large amplification in magnetic vortex gyration in magnetic vortex transistor is proposed to be maintained for a network of vortex transistor. The above observations promote the magnetic vortex transistors to be used in complex circuits and logic operations.