Non-Ohmic Properties in n-Type InSb

Contrary to earlier views, it was disclosed that (1) the donor band distinctively exists below the conduction band even in absence of magnetic field, and, at T ≦4.2°K, most electrons are in the donor band in thermal equilibrium but are abruptly ionized to the conduction band by an electric field within 0.1 v/cm, while (2) the non-linear quantum-limit effect, predicted by Kazarinov and Skobov, explicity occurs at electric fields higher than ∼1 v/cm and is replaced by the classical-limit effect after showing a resistivity minimum at ∼40 v/cm. These new conclusions are based on extensive measurements of resistivity and Hall coefficient by null method for n -InSb with N D - N A ∼1×10 14 cm -3 as a function of electric field up to 200 v/cm with and without a transverse magnetic field below 12 k -gauss between 1.8 and 77°K. Effects of magnetic field and temperature on the carrier concentration in the conduction band and the mobility in the donor band are also described.