Modeling tools for nanoelectronics

In this talk I will introduce the so-called DFT+NEGF method for simulations of electron transport in nanoscale junctions.

This method is based on the nonequilibrium Green's function (NEGF) technique that allows to describe open quantum systems and to compute transport properties, in combination with density functional theory (DFT) to provide realistic atomistic and electronic descriptions of nanoscale devices.

More specifically, I will provide an overview of the TranSIESTA [1] and Inelastica [2] DFT+NEGF codes, and describe some of our recent applications of these, e.g., the proposal of an electron beam splitter realized with crossed graphene nanoribbons [3] and a study to understand inelastic electron tunneling spectroscopy (IETS) experiments of graphene/SiC samples [4].

References

[1] Brandbyge, Mozos, Ordejón, Taylor, Stokbro, Phys. Rev. B 65, 165401 (2002); Papior, Lorente, Frederiksen, García, Brandbyge, Comp. Phys. Comm. 212, 8-24 (2017); https://launchpad.net/siesta.
[2] Frederiksen, Paulsson, Brandbyge, Jauho, Phys. Rev. B 75, 205413 (2007); https://github.com/tfrederiksen/inelastica/.
[3] Brandimarte, Engelund, Papior, Garcia-Lekue, Frederiksen, Sánchez-Portal, J. Chem. Phys. 146, 092318 (2017).
[4] Minamitani, Arafune, Frederiksen, Suzuki, Shahed, Kobayashi, Endo, Fukidome, Watanabe, Komeda, Phys. Rev. B 96, 155431 (2017).