  A study of magneto-transport through quantum dots is presented. The model
allows to analyze tunnelling both from bulk-like contacts and from 2D
accumulation layers. The fine features in the I-V characteristics due to the
quantum dot states are known to be shifted to different voltages depending upon
the value of the magnetic field. While this effect is also well reproduced by
our calculations, in this work we concentrate on the amplitude of each current
resonance as a function of the magnetic field. Such amplitudes show
oscillations reflecting the variation of the density of states at the Fermi
energy in the emitter. Furthermore the amplitude increases as a function of the
magnetic field for certain features while it decreases for others. In
particular we demonstrate that the behaviour of the amplitude of the current
resonances is linked to the value of the angular momentum of each dot level
through which tunnelling occurs. We show that a selection rule on the angular
momentum must be satisfied. As a consequence, tunnelling through specific dot
states is strongly suppresses and sometimes prohibited altogether by the
presence of the magnetic field. This will allow to extract from the
experimental curves detailed information on the nature of the quantum dot
wavefunctions involved in the electronic transport. Furthermore, when
tunnelling occurs from a 2D accumulation layer to the quantum dot, the presence
of a magnetic field hugely increases the strength of some resonant features.
This effect is predicted by our model and, to the best of our knowledge, has
never been observed.
