39 research outputs found
Spin Hall effect in a Kagome lattice driven by Rashba spin-orbit interaction
Using four-terminal Landauer-B\"{u}ttiker formalism and Green's function
technique, in this present paper, we calculate numerically spin Hall
conductance (SHC) and longitudinal conductance of a finite size kagome lattice
with Rashba spin-orbit (SO) interaction both in presence and absence of
external magnetic flux in clean limit. In the absence of magnetic flux, we
observe that depending on the Fermi surface topology of the system SHC changes
its sign at different values of Fermi energy, along with the band center.
Unlike the infinite system (where SHC is a universal constant ), here SHC depends on the external parameters like SO coupling strength,
Fermi energy, etc. We show that in the presence of any arbitrary magnetic flux,
periodicity of the system is lost and the features of SHC tends to get reduced
because of elastic scattering. But again at some typical values of flux
($\phi=1/2, 1/4, 3/4..., etc.) the system retains its periodicity depending on
its size and the features of spin Hall effect (SHE) reappears. Our predicted
results may be useful in providing a deeper insight into the experimental
realization of SHE in such geometries.Comment: 10 pages, 10 figure
Magneto-transport in a mesoscopic ring with Rashba and Dresselhaus spin-orbit interactions
Electronic transport in a one-dimensional mesoscopic ring threaded by a
magnetic flux is studied in presence of Rashba and Dresselhaus spin-orbit
interactions. A completely analytical technique within a tight-binding
formalism unveils the spin-split bands in presence of the spin-orbit
interactions and leads to a method of determining the strength of the
Dresselhaus interaction. In addition to this, the persistent currents for
ordered and disordered rings have been investigated numerically. It is observed
that, the presence of the spin-orbit interaction, in general, leads to an
enhanced amplitude of the persistent current. Numerical results corroborate the
respective analytical findings.Comment: 7 pages, 7 figure