Keywords
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Spin to pseudo‑spin conversion by which the non‑equilibrium normal sublattice pseudo‑spin
polarization could be achieved by magnetic field has been proposed in graphene. Calculations have
been performed within the Kubo approach for both pure and disordered graphene including vertex
corrections of impurities. Results indicate that the normal magnetic field Bz produces pseudo‑spin
polarization in graphene regardless of whether the contribution of vertex corrections has been taken
into account or not. This is because of non‑vanishing correlation between the σz and τz provided by the
co‑existence of extrinsic Rashba and intrinsic spin–orbit interactions which combines normal spin and
pseudo‑spin. For the case of pure graphene, valley‑symmetric spin to pseudo‑spin response function
is obtained. Meanwhile, by taking into account the vertex corrections of impurities the obtained
response function is weakened by several orders of magnitude with non‑identical contributions of
different valleys.
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Abstract
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Spin to pseudo‑spin conversion by which the non‑equilibrium normal sublattice pseudo‑spin
polarization could be achieved by magnetic field has been proposed in graphene. Calculations have
been performed within the Kubo approach for both pure and disordered graphene including vertex
corrections of impurities. Results indicate that the normal magnetic field Bz produces pseudo‑spin
polarization in graphene regardless of whether the contribution of vertex corrections has been taken
into account or not. This is because of non‑vanishing correlation between the σz and τz provided by the
co‑existence of extrinsic Rashba and intrinsic spin–orbit interactions which combines normal spin and
pseudo‑spin. For the case of pure graphene, valley‑symmetric spin to pseudo‑spin response function
is obtained. Meanwhile, by taking into account the vertex corrections of impurities the obtained
response function is weakened by several orders of magnitude with non‑identical contributions of
different valleys. This valley‑asymmetry originates from the inversion symmetry breaking generated
by the scattering matrix. Finally, spin to pseudo‑spin conversion in graphene could be realized
as a practical technique for both generation and manipulation of normal sublattice pseudo‑spin
polarization by an accessible magnetic field in a easy way. This novel proposed effect not only offers
the opportunity to selective manipulation of carrier densities on different sublattice but also could
be employed in data transfer technology. The normal pseudo‑spin polarization which manifests it
self as electron population imbalance of different sublattices can be detected by optical spectroscopy
measurements.
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