It is a narrow-gap semiconductor material.

Narrow-Gap Semiconductors.

He has investigated narrow-gap semiconductors and liquid crystals and was engaged in several interdisciplinary studies on the effect of non-ionizing electromagnetic radiation in biological systems.

In narrow-gap semiconductors with inversion center EDSR can emerge due direct coupling of electric field to the anomalous coordinate , see Spin-orbit interaction.

On the other hand, in narrow-gap semiconductors this variation of energy is considerable and therefore external pressure or magnetic field may serve the purpose of tuning into the resonance of one-phonon interband transition.

It is a narrow-gap semiconductor material from the III-V group used in infrared detectors, including thermal imaging cameras, FLIR systems, infrared homing missile guidance systems, and in infrared astronomy.