We calculate the excitonic transition energy in T-shaped quantum well
wires. The complexity of the valence band is taken into account. This
leads to a description of the exciton where the hole is bound mainly t
o the electron when the wire valence band confinement potential is too
weak. This allows one a comparison with experimental results obtained
in Ga1-xAlxAs T-shaped quantum well wires with widths of 70 and 50 An
gstrom and x=0.3 and 0.35. (C) 1997 Elsevier Science Ltd.