Electronic and optical properties of functionalized germanene quantum dot (GeQD)

The effect of edge functionalization with hydrogen, fluorine, and chlorine atoms on electronic, structural, and optical properties of germanene nanoflakes has been investigated within the framework of Density Functional Theory. The HOM O-LUM O energy gap in functionalized structures varying from 1.05 eV to 0.88eV has been observed. The electronic properties of functionalized systems have been studied by charge density profile and by Scanning Tunnelling Microscope. The effect of the external electric field has been studied. The optical behaviour shows a red shift for halogens (-F, -Cl) functionalization compared to hydrogenation. The Plasmon frequencies have been captured in functionalized flakes in the Visible and IR regions.