  We demonstrate edge-emitting exciton-polariton (polariton) lasing from 5 to
300 K and amplification of non-radiative guided polariton modes within ZnO
waveguides. The mode dispersion below and above the lasing threshold is
directly measured using gratings present on top of the sample, fully
demonstrating the polaritonic nature of the lasing modes. The threshold is
found to be similar to that of radiative polarions in planar ZnO microcavities.
These results open broad perspectives for guided polaritonics by allowing an
easier and more straightforward implementation of polariton integrated circuits
exploiting fast propagating polaritons.
