  We present the realization of mid-infrared waveguide by ultrafast laser
inscription technique in a chalcogenide glass. Our approach is based on
multicore waveguide that consists in an alignment on a mesh of positive
refractive index channels placed parallel to each other. Two different meshes
are investigated with different refractive index contrasts between the channel
and the glass matrix. A detailed analysis of the performances at a wavelength
of 4.5 $\mu$m shows propagation losses of 0.20 $\pm$ 0.05 dB/cm and coupling
efficiencies higher than 60 %.
