Nonlinear polaritons (IMAGE) University of Warsaw, Faculty of Physics Caption On the left: a spatial cross-section of the studied structure. Two optical microcavities (broad black stripes) are visible, surrounded by a multilayer Bragg mirrors. The image shows the spatial distribution of magnesium. It was obtained in a transmission electron microscope in the measurement of energy dispersion X-ray spectroscopy. On the right: angularly resolved emission spectrum of a system of two coupled optical microcavities recorded for excitation power above the polariton lasing threshold. The white lines represent the calculated polariton levels. Parametric polariton scattering is visible as bright points inside the blue rectangles. (Source: K. Sobczak, CNBCh UW, K. Sawicki, Faculty of Physics UW) Credit K. Sobczak, CNBCh UW, K. Sawicki, Faculty of Physics UW Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. Adaptations must be shared under the same terms. License CC BY-NC-SA Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.