LONGITUDINAL CONDUCTIVITY OF A BOLTZMANN ELECTRON-GAS IN N-INSB IN THE QUANTUM LIMIT IN THE MAGNETIC-FIELD

The longitudinal conductivity (i.e., that along the magnetic field) of n-InSb due to an interaction of electrons with ionized impurities has been measured in the quantum limit in the magnetic field under conditions corresponding to a Boltzmann statistics of the electrons. For samples with an electron density n = 10(15) cm-3 the results are close to the theoretical predictions of Agyres and Adams [Phys. Rev. 104, 900 (1956)]. Their theory predicts a decrease in the resistance when a strong field is applied. As the electron density decreases, the difference between the experimental and theoretical results increases, and the magnetoresistance goes from negative to positive.