摘要
The spin Hall and spin Nernst effects in graphene are studied based on Green's function formalism. We calculate intrinsic contributions to spin Hall and spin Nernst conductivities in the Kane-Mele model with various structures. When both intrinsic and Rashba spin-orbit interactions are present, their interplay leads to some characteristics of the dependence of spin Hall and spin Nernst conductivities on the Fermi level. When the Rashba spin--orbit interaction is smaller than intrinsic spin-orbit coupling, a weak kink in the conductance appears. The kink disappears and a divergence appears when the Rashba spin-orbit interaction enhances. When the Rashba spin-orbit interaction approaches and is stronger than intrinsic spin-orbit coupling, the divergence becomes more obvious.
The spin Hall and spin Nernst effects in graphene are studied based on Green's function formalism. We calculate intrinsic contributions to spin Hall and spin Nernst conductivities in the Kane-Mele model with various structures. When both intrinsic and Rashba spin-orbit interactions are present, their interplay leads to some characteristics of the dependence of spin Hall and spin Nernst conductivities on the Fermi level. When the Rashba spin--orbit interaction is smaller than intrinsic spin-orbit coupling, a weak kink in the conductance appears. The kink disappears and a divergence appears when the Rashba spin-orbit interaction enhances. When the Rashba spin-orbit interaction approaches and is stronger than intrinsic spin-orbit coupling, the divergence becomes more obvious.
基金
Project supported by the National Natural Science Foundation of China (Grant No. 10934010)
the National Basic Research Program of China (Grant Nos. 2011CB921502 and 2012CB821305)