Disorder in Silicon Nanowire Arrays for Photovoltaic Applications.

Abstract

We study the effect of non-uniform radii on the optical absorption of silicon nanowire arrays. Whilst previous studies have shown that radius disorder can increase the efficiency, the mechanism is unclear. To elucidate this we study structures with a small supercell, forming a regular nanowire array with two distinct radii. We find that these arrays have new electromagnetic resonances, not present in arrays with uniform radii, leading to increased absorption.