31 research outputs found
Emergence of electromotive force in precession-less rigid motion of deformed domain wall
Recently it has been recognized that the electromotive force (emf) can be
induced just by the spin precession where the generation of the electromotive
force has been considered as a real-space topological pumping effect. It has
been shown that the amount of the electromotive force is independent of the
functionality of the localized moments. It was also demonstrated that the rigid
domain wall (DW) motion cannot generate electromotive force in the system.
Based on real-space topological pumping approach in the current study we show
that the electromotive force can be induced by rigid motion of a deformed DW.
We also demonstrate that the generated electromotive force strongly depends on
the DW bulging. Meanwhile results show that the DW bulging leads to generation
of the electromotive force both along the axis of the DW motion and normal to
the direction of motion
Modified spin-orbit couplings in uniaxially strained graphene
Intrinsic and Rashba spin-orbit interactions in strained graphene is studied
within the tight-binding (TB) approach. Dependence of Slater-Koster (SK)
parameters of graphene on strain are extracted by fitting the \emph{ab initio}
band structure to the TB results. A generalized low-energy effective
Hamiltonian in the presence of spin-orbit couplings is proposed for strained
graphene subjected to an external perpendicular electric field. Dependence of
the modified Rashba strength and other parameters of effective Hamiltonian on
the strain and electric field are calculated. In order to analyze the influence
of the applied strain on the electronic properties of the graphene, one must
take into account the lattice deformation, modifications of the hopping
amplitudes and shift of the Dirac points. We find that using the strain it is
possible to control the strength of Rashba and intrinsic spin-orbit couplings
as well as energy gap at the shifted Dirac points. Meanwhile, the strain
slightly modifies the topology of low-energy dispersion around the Dirac
points. We describe the SOCs induced energy splitting as a function of strain
The role of the Rashba coupling in spin current of monolayer gapped graphene
In the current work we have investigated the influence of the Rashba
spin-orbit coupling on spin-current of a single layer gapped graphene. It was
shown that the Rashba coupling has a considerable role in generation of the
spin-current of vertical spins in mono-layer graphene. The behavior of the
spin-current is determined by density of impurities. It was also shown that the
spin-current of the system could increase by increasing the Rashba coupling
strength and band-gap of the graphene and the sign of the spin-current could be
controlled by the direction of the current-driving electric field