Tiny, tangled wires keep photons from reflecting

Tiny, tangled wires keep photons from reflecting. The predominant material in most solar panels is shiny, crystalline silicon coated with an efficiency-improving antireflective substance. Because the Sun moves across the sky from dawn to dusk, the best antireflectors are effective for a wide range of incidence angles and for all colors of visible light. Yasha Yi and colleagues have recently devised a novel antireflecting structure with those desirable qualities. As shown in the scanning electron microscope image, the antireflecting layer consists of nanometer-thin wires that attach to the crystalline Si surface (lower edge of the figure) at random angles. The wires have a core of Si (white) and are clad with silicon oxide (gray). The varying index of refraction from cladding to core gives the wires their antireflecting properties; the random orientation of the wires makes the structure effective over a wide range of angles. To generate their tangled...