Angle-dependent resonant light absorption of polariton states in one-dimensional ZnO microcavities

We demonstrate the experimental observation of the angle-dependent resonant light absorption of excitonic polariton states in a single onedimensional ZnO microcavity at room temperature by using the guided photoluminescence of a ZnO microwire as a micro light source. Clear mappings of polariton absorption, showing distinct dispersion curves, are observed. As a complementary optical technique to photoluminescence, this microabsorption spectroscopy resonantly excites the cavity-polariton modes without creating free excitons, and provides a direct evidence of the strong coupling between excitons and cavity modes in the ZnO microwire.