Dielectric constant and anomalous magnetoresistance of zero-gap semiconductors

Abstract

It is shown that for a zero-gap semiconductor the static dielectric constant at infinite wavelength ($\overrightarrow{\mathrm{q}}=0\mathrm{}$) and zero temperature contains a magnetic-field-dependent term of the form of $H^{-\frac{1}{2}}$. Because of this anomalous term, both the longitudinal and the transverse classical magnetoresistance for a $p$-type sample are expected to have a dependence on the magnetic field other than the usual $H^2$ behavior in the low-temperature region.