Indium gallium nitride (${\mathrm{In}}_x{\mathrm{Ga}}_{1-x}\mathrm{N}$)

Indium gallium nitride is the semiconductor alloy $\mathrm{I}{\mathrm{n}}_{\mathrm{x}}\mathrm{G}{\mathrm{a}}_{1-\mathrm{x}}\mathrm{N}$. Changing the indium fraction changes its electronic band structure and optical transition energies.

This compositional tuning supports light emission over different wavelength ranges. Strain and phase uniformity also matter, so wavelength is not set by composition independently of the material's structure.