ABSTRACT
The interaction of photons with molecules and materials, resulting in the absorption and production of radiation, is a fundamental component of many energy devices. This chapter discusses the general properties of light absorption and luminescence in solids, nanostructured materials, and molecules. It addresses the general concepts of quantum efficiency and quantum yield that govern the conversion between electricity and light. The chapter reviews basic recombination mechanisms in semiconductors and the methods of determination of carrier lifetime. It considers the description of the absorption processes and the light-emitting processes. Incident radiation on a material results in different types of interactions. The incident light can be reflected at any surface. The chapter also discusses light emission properties of the textured cell compared with the blackbody radiation. It illustrates the higher light emission of a textured silicon diode compared to planar diodes.
