Improving the efficiency of GaAs solar cells using a double semi-transparent carbon nanotubes thin layerSeyed Nooreddin Jafari, Abbas Ghadimi and Saeed RouhiEur. Phys. J. Appl. Phys., 88 2 (2019) 20401DOI: https://doi.org/10.1051/epjap/2019190146