Pressure and Temperature Dependences ofCdxHg1−xTeAlloy Hall Mobilities

Abstract

The pressure and temperature dependences of the Hall mobilities ${\mu }_H$ of ${\mathrm{Cd}}_x{\mathrm{Hg}}_{1-x}\mathrm{Te}$ alloys, with $x=0.07, 0.095, 0.13, \mathrm{and} 0.18$ have been measured from 4.2 to 77 °K at pressures up to 8.40 katm. The ${\mu }_H$ appear to be determined primarily by lattice scattering at the highest temperatures and by ionized impurity scattering at 4.2 °K. A minimum in ${\mu }_H$ vs $T$ at approximately 10 °K is observed for the $x=0.13\mathrm{} \mathrm{and} 0.18$ samples. There is little variation with pressure of the temperature associated with the minimum. The variation of ${\mu }_H$ with energy gap $E_G$ as determined by pressure measurements on the $x=0.07\mathrm{} \mathrm{and} 0.13$ samples is asymmetric about $E_G=0\mathrm{}$, in accordance with a recent theory of ionized impurity scattering in these systems which takes the variation of the dielectric constant with carrier concentration into account.