Abstract
In this work, the absorption efficiency (Qabs) of GaAs/InAs core-shell nanowires on Si (111) for normal incident light is investigated. Simulations show the influences of NW diameter on the Qabs of the structure. Using the finite-difference time-domain (FDTD) and Mie theory, the highest Qabs for NW solar cells were obtained at a core diameter of 220 nm and a shell thickness of 35 nm. Additionally, the wavelength-dependent external quantum efficiencies (EQEs) for NWs were investigated. Numerical simulation of current density-voltage (J-V) characteristics of nanowires under illuminated conditions was studied. Furthermore, the band structure for GaAs core-shell nanowires was calculated. Optimized geometric parameters are obtained through the simulations.
•We investigated the effect of the wavelength on the Qabs by using Lumerical FDTD solutions.•First, the effect of the wavelength on the Qabs with varying core diameters with a fixed shell thickness of about 35 nm.•Second, we study the effect of the wavelength on the Qabs with varying shell thickness of the NW.•The variation of the EQE with the wavelength was investigated for different NW diameters.•Finally, J-V characteristics have been calculated under standard AM1.5G illumination conditions.