Nanowire solar cells are of great interests due to their promising prospects as nano-electronic power sources. Here, wepropose a standing semiconductor-dielectric core-shell nanocone array (CSNCA). We find that the CSNCA structure cannot only concentrate the incident light into the structure, but also confine most of the concentrated light to thesemiconductor (InP) core region, which enhances remarkably the light absorption of the more material-savingsemiconductor core. Thanks to the gradient of diameter size along the axial in cone, incident light of different wavelengthscan be maximally coupled into the core. We find guided resonance features along the radial and FP-resonant features alongthe axial by analyzing the electric field patterns at the absorption spectrum peaks. The CSNCA can support multiple higherorderHE modes, in comparison to the bare nanocone array (BNCA). Interaction of the adjacent higher-order HE modesresults in broadband light absorption enhancement in the solar radiation spectrum. Carrier generation rates (G) have alsobeen studied when the electrical part is discussed. CSNCAs show a unique advantage in G distribution. Results based ondetailed balance analysis demonstrate that the core-shell design gives rise to higher short-circuit current and open-circuitvoltage, and thus higher power conversion efficiency. This advantage is more apparent in thin structures compared withthe thick ones. Detailed research is focused on the 1 μm high CSNCAs, and a remarkable enhancement (42.2%) is gainedcompared with the BNCAs. Our study shows that the CSNCAs can be promising candidates for application in superminiature photodetectors, nanometer power sources and ultra-thin film solar cells.
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