  III-V materials show a wide range of gaps making them ideal for the design of
high efficiency solar cells. This chapter reviews relevant growth methods and
material properties of these materials and discusses methods of combining
heterogeneous materials, demonstrating the flexibility of design possible with
these materials. The fundamental loss mechanisms of solar cells are analysed
and quantified as a prelude to analysing high efficiency cell designs in
single, tandem, and triple junction solar cells. The detailed analysis of loss
mechanisms is used to obtain understanding of the limiting behaviour of these
designs, and show that bulk cells remain dominated by non-radiative losses
despite unity ideality factors. To conclude, this is contrasted with the
operating regime of nanostructured solar cells which can be shown to operate in
a radiatively dominated mode, and which therefore approach ideal solar cell
efficiency limits.
