Accurate atomistic modelling of solar cells has so-far been prohibited since it requires simultaneous description of both electron-photon and electron-phonon interactions in the device. PhD student Mattias Palsgaard has overcome this problem by combining the Special Temperature Displacement approximation for electron-phonon interaction with a Non Equilibrium Greens Function (NEGF) description of electron-photon interaction. The method has been applied to silicon solar cell device geometries and the results are in excellent agreement with experimental data. The results are reported in the July edition of Physical Rev. Applied  and has been selected as the editors choice. The method enables new insight into solar cell devices, and the editor find that the “Excellent agreement with experiment shows that this method could be widely useful for physicists and engineers alike to benchmark tomorrow's optoelectronic devices” .
Structure and cell used in the calculation of the 19.6-nm silicon p-n junction, with n=2x1019 cm-3 and Local density of states along the transport direction of the silicon p-n junction on a logarithmic scale.
All the methods used in the paper are available in the QuantumATK O.2018.6 release and they are described in the tutorials:
 M.Palsgaard, T. Markussen, T. Gunst, M. Brandbyge, and K. Stokbro, "Efficient First-Principles Calculation of Phonon-Assisted Photocurrent in Large-Scale Solar-Cell Devices", Phys. Rev. App. 10, 014026 (2018).