Friday, March 23, 2012

1203.4880 (Wen-Yu Shan et al.)

Spin-orbit scattering in quantum diffusion of massive Dirac fermions    [PDF]

Wen-Yu Shan, Hai-Zhou Lu, Shun-Qing Shen
Effect of spin-orbit scattering on quantum diffusive transport of two-dimensional massive Dirac fermions is studied by the diagrammatic technique. The quantum diffusion of massive Dirac fermions can be viewed as a singlet Cooperon in the massless limit and a triplet Cooperon in the large-mass limit. The spin-orbit scattering behaves like random magnetic fields only to the triplet Cooperon, and suppresses the weak localization of Dirac fermions in the large-mass regime. This behavior suggests an experiment to detect the weak localization of bulk subbands in topological insulator thin films, in which a narrowing of the cusp of the negative magnetoconductivity is expected after doping heavy-element impurities. Finally, a detailed comparison between the conventional two-dimensional electrons and Dirac fermions is presented for impurities of orthogonal, symplectic, and unitary symmetries.
View original: http://arxiv.org/abs/1203.4880

No comments:

Post a Comment