Approaching the theoretically limiting open circuit voltage (V_oc) of solar cells is crucial to optimize their photovoltaic performance. Here, we demonstrate experimentally that nanostructured layers can achieve a fundamentally larger Fermi level splitting, and thus a larger V_oc, than planar layers. By etching tapered nanowires from planar indium phosphide (InP), we directly compare planar and nanophotonic geometries with the exact same material quality. We show that the external radiative efficiency of the nanostructured layer at 1 sun is increased by a factor 14 compared to the planar layer, leading to a 70 mV enhancement in V_oc. The higher voltage arises from both the enhanced outcoupling of photons, which promotes radiative recombination, and the lower active material volume, which reduces bulk recombination. These effects are generic and promise to enhance the efficiency of current record planar solar cells made from other materials as well.

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The mechanical characteristics of the long-chain double-stranded DNA (dsDNA) molecule under the axial stretching and lateral unzipping are studied by the clustered atomistic-continuum method (CACM). The CACM consisted of the clustered atom method (CAM) and the atomistic-continuum method (ACM). The CAM treats the specific atomic group as the superatom, and the ACM describes the chemical binding energies between (super)atoms by virtual elements. The Newtonian based model of the dsDNA includes the superatoms of the backbones/base pairs and the virtual elements of the stacking energies/hydrogen bonds. The effective properties of the superatoms are numerically extracted from the single-stranded DNA experiments. Good agreements were achieved between the dsDNA numerical results and the single molecular experimental results. Via the simulation of stretching dsDNA, the mechanical responses, including the twisting of the backbone and variation of the elastic deformation energy and stacking energy can be elucidated. Moreover, the predictive capability of the dsDNA, CACM model is then examined. Furthermore, the dsDNA model with sequential information is subjected to the unzipping loading, and the in silico results reveal that the sliding of the backbones and the sequential dependent mechanical responses.@en