  We present results on electron transport in quasi-one dimensional (1D)
quantum wires in GaAs/AlGaAs heterostructures obtained using an asymmetric
confinement potential. The variation of the energy levels of the spatially
quantized states is followed from strong confinement through weak confinement
to the onset of two-dimensionality. An anticrossing of the initial ground and
first excited states is found as the asymmetry of the potential is varied
giving rise to two anticrossing events which occur on either side of symmetric
confinement. We present results analysing this behaviour and showing how it can
be affected by the inhomogeneity in background potential. The use of an
enhanced source-drain voltage to alter the energy levels is shown to be a
significant validation of the analysis by showing the formation of double rows
of electrons which correlate with the anticrossing.
