We present experimental measurements of the resonance of the large intensity dependence of refractive index in InSb near the band-gap energy at 77 K and derive a semiempirical theory for this effect which fits the measurements well, both in absolute magnitude and wavelength dependence, using only measurable parameters. The size of the effect in other nondegenerate direct-band-gap III-V compound semiconductors and at other temperatures is predicted.

No abstract