The description of spin transport in organic devices poses a formidable challenge to theory and modeling. One has to understand first how spins are injected from a ferromagnetic metal into an organic material and then a theory should be at hand for describing spin transmission across the organic. These two aspects require a theory which is microscopic in nature, but also scalable to large and complex organic crystals, namely they call for a fundamental multi-scale approach.<br/><br/>In this talk I will review how such a multi-scale approach can be constructed. Firstly I will look at the problem of spin injection into an organic molecular layer. In particular I will correlated electronic structure theory results with spin- and energy-resolved two photon photoemission data. Such comparison will reveal that electron-phonon coupling plays an important role in determining the spin polarization of injected current. Secondly, I will present our multi-scale approach to the calculation of the mobility and spin-relaxation length of organic materials. In particular I will show how a coarse-grained theory can be obtained by combining density functional theory with maximally localized Wannier functions, and how this can be solved with Monte Carlo techniques. Results on rubrene and durene single crystals will be presented.

Spin transport in organic materials: From single molecules to crystals

249th National Meeting (2015)

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