Quantitative theory for the quantum interference effect in the transverse magnetoresistance of pure magnesium

Abstract

A new quantitative theory is developed to calculate from first principles the transverse magnetoresistance of Mg for the special case in whichH is parallel to a [10$\bar 1$0]-type axis andJ is parallel to a [11$\bar 2$0]-type axis. For this case, magnetic breakdown produces a multiply coupled network of interfering electron trajectories which generate large-amplitude quantum oscillations in the transverse magnetoresistance. It is shown that two distinct regimes of quantum transport exist for these oscillations and that this theory can be used to derive the electron quantum state lifetime τ from experimental data. The sensitivity of this effect to τ extends the experimentally accessible range by four orders of magnitude from about 10⁻¹² to 10⁻⁸ sec. In addition, since the quantum interference oscillations are essentially insensitive to the temperature dependence of the Fermi-Dirac distribution function, this effect is ideally suited to study the quantum state lifetime dependence on electron-electron scattering.