Nanowire Solar Cell 2D: Radial-Junction Light Trapping

Vertical silicon-nanowire arrays with a radial (core–shell) p–n junction let a solar cell absorb light along a long axial path while collecting charge over a short radial one — decoupling two requirements that fight each other in a planar cell. This simulator renders the array as a labeled multi-panel 2D scene: a side-on cross-section shows photons falling in and being absorbed at a Beer–Lambert-distributed depth, a pannable top-down view shows the electron–hole pair born at that depth diffusing radially out to the shell junction (collected) or dying before it arrives (recombined), and three live curve panels plot absorption, collection and the light-trapping factor against the current sliders. Four controls — wire radius, array height, minority-carrier diffusion length and packing fill fraction — drive it all, so you can see directly why thin, tall, well-spaced nanowires can outperform an equivalent planar absorber.