ABSTRACT
In recent years, great attention has been focused on finding the ideal quan-
tum bit (qubit) to perform quantum computation, where it is necessary
to create a linear superposition of states with a long coherence time [1].
With respect to the general criteria for quantum computers [2], semicon-
ductor quantum dots (QD) appear as good candidates. In particular, self
assembled quantum dots that confine electrons and holes down to 10 nm
length scale and can be individually addressed [3], have a strong potential
for the realisation of an elementary quantum gate in condensed matter.
Two possible routes towards this aim have been investigated up to now:
