Small-Gap Semiconductors in Crossed Magnetic and Electric Fields

It is demonstrated theoretically that in a small-gap semiconductor with large spin-orbit interaction energy a sufficiently strong transverse electric field destroys the Landau diamagnetic quantization but not the Pauli paramagnetic quantization of the conduction band. In a zero-gap semiconductor of the HgTe type the transverse electric field below the critical strength causes crossing of electron and heavy-hole Landau levels, thus inducing a semiconductor-semimetal transition.