Fig. 1. (Color online) (a) Schematic of the GaAs solar cell with nano-sphere array in side view. (b) Schematic top view of the nano-sphere surface array.

Fig. 2. (Color online) The conversion efficiency as a function of radius for different D value.

Fig. 3. (Color online) Calculated spectral distribution graph for (a) absorption, (b) reflection and (c) transmission for different D values with n = 2 and R = 0.6 μm.

Fig. 4. (Color online) Shows the contour map for photon absorption between radius and wavelength with D of 0 μm.

Fig. 5. (Color online) Calculated spectral distribution graph for (a) absorption, (b) reflection and (c) transmission for different R values.

Fig. 6. Illustration of the overall cell efficiency as a function of the refractive index of nano-spheres (n).

Fig. 7. J–V characteristics of the GaAs based solar cells.