Regensburg 2010 – wissenschaftliches Programm
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HL: Fachverband Halbleiterphysik
HL 26: Spin-controlled Transport II
HL 26.1: Vortrag
Dienstag, 23. März 2010, 14:00–14:15, H14
Graphene gets picky with the different formalisms for deriving spin-coherent Boltzmann equations — •Janik Kailasvuori — Max Planck Institut für Physik komplexer Systeme
Semiclassical spin-coherent kinetic equations can be derived from quantum theory with many different approaches. In graphene, where the pseudospin-orbit interaction constitutes the entire kinetic energy, the difference actually manifests itself and determines the precise value of electron-hole coherence authored quantum correction to the Drude conductivity ∼ e2h ℓ kF. We derive this correction analytically for single and multilayer graphene with arbitrary impurities and find different results with different approaches. We also find that the often neglected principal value terms in the collision integral are very important. Neglecting them gives a leading correction only of order (ℓ kF)−1, whereas including them can give a correction of order (ℓ kF)0. In the latter scenario the correction could be accurately determined with simple linear regression of the conductivity in the Boltzmann regime. Thus graphene may offer an excellent setting for experimentally settling conflicts between different approaches.