COHERENT MAGNETOTUNNELING IN COUPLED QUANTUM-WELLS FOR DIFFERENT LANDAU-LEVELS

In this work, we have studied the coherent tunneling oscillations of electrons in a Ga1-xAlxAs-GaAs asymmetric double quantum well heterostructure under external applied electric and magnetic fields along the growth direction of the structure. In this coupled quantum well system, it is found that magnetic quantization collapses the resonant condition for coherent oscillations between the coupled quantum well states into a discrete set of coherent tunneling channels. These tunneling channels depend on the magnetic field value and on the Landau level number. We show the possibility of a direct observation of these tunneling processes by means of an oscillating luminescence signal. © 1992.