  The optical selection rules in epitaxial quantum dots are strongly influenced
by the orientation of their natural quantization axis, which is usually
parallel to the growth direction. This configuration is well suited for
vertically emitting devices, but not for planar photonic circuits because of
the poorly controlled orientation of the transition dipoles in the growth
plane. Here we show that the quantization axis of gallium arsenide dots can be
flipped into the growth plane via moderate in plane uniaxial stress. By using
piezoelectric strain actuators featuring strain-amplification we study the
evolution of the selection rules and excitonic fine-structure in a regime, in
which quantum confinement can be regarded as a perturbation compared to strain
in determining the symmetry properties of the system. The experimental and
computational results suggest that uniaxial stress, may be the right tool to
obtain quantum light sources with ideally oriented transition dipoles and
enhanced oscillator strengths for integrated quantum photonics.
