Giant nonlinearity in Zero-Gap Semiconductor Superlattices

Using an effective medium approach, we describe how by combining mercury-cadmium-telluride semiconductor alloys with band gap energies of opposite signs it may be possible to design a superlattice where the electrons have isotropic zero-effective mass and a single valley linear energy-momentum dispersion. We demonstrate that because of the zero-mass property, the superlattice may have a strong nonlinear response under the action of an external electromagnetic field.