The confined optical modes in photonic wires formed by lithography of plana
r microcavities are studied by angle-resolved photoluminescence spectroscop
y. These modes exhibit dispersion along the length of the wire and are conf
ined for motion perpendicular to the wires in plane. Polarization-dependent
spectroscopy shows a splitting between modes with electric field along and
perpendicular to the wires, which is in agreement with detailed calculatio
ns. [S0163-1829(98)06148-7].