We have observed strong oscillations on the current versus magnetic field c
haracteristics of a semiconductor multiquantum well with the magnetic field
applied perpendicular to the layers. We associate these oscillations to re
sonant tunneling without conservation of Landau level index and to the open
ing of a new channel of intrawell inter-subband relaxation. (C) 1998 Elsevi
er Science B.V. All rights reserved.