MAGNETO-OSCILLATIONS OF THE TUNNELING CURRENT BETWEEN 2-DIMENSIONAL ELECTRON-SYSTEMS

The tunnelling current caused by electron transfer between two-dimensi onal layers is calculated as a function of the magnetic field applied perpendicular to the layers and level splitting of the tunnel-coupled states. The elastic scattering of the electrons is taken into consider ation. Analytical results describing both the tunnelling relaxation ra te of photoexcited electrons and the tunnelling current between the in dependently contacted quantum wells are obtained for two regimes: (i) that of small magnetic fields, for which the Landau quantization is su ppressed by the scattering and the oscillating part of the current sho ws nearly harmonic behaviour; and (ii) that of high magnetic fields, f or which the Landau levels are well defined and the current shows a se ries of sharp peaks corresponding to resonant magnetotunnelling. In th e latter case, we used two alternative approaches: the self-consistent Born approximation method and the path-integral method, and demonstra ted that the results obtained show reasonable agreement for both of th ese methods. The influence of the interlayer correlation of the scatte ring on the first magnetotunnelling peak is also discussed.