Terahertz magnetospectroscopy of pseudo-relativistic fermions in HgCdTe alloys under hydrostatic pressure

We report on terahertz (THz) magnetospectroscopy of Hg 1-x Cd x Te (MCT) epitaxial alloys with various cadmium content (from x = 0.15 to x = 0.17). Additionally some magnetospectroscopy investigations were performed as a function of hydrostatic pressure. We show that all experimental data can be perfectly interpreted within the pseudo-relativistic description assuming E g = 2mc2 where E g is the band gap, m is the fermion rest mass and c is the constant. Remarkably, the experimental results for all the samples are consistently described by using constant velocity c = 1.0•106 m/s (close to Fermi velocity in graphene) independent of hydrostatic pressure and Cd content.