Polaritons in periodic potentials are useful for understanding the physics of many-body systems and exploring applications in optoelectronics. Recent experiments by Long Zhang, Wei Xie and an international collaboration from China, Russia, Mexico, the USA and the UK suggest that an effect known as weak lasing in one-dimensional polaritons in superlattices has now been observed at room-temperature. A structure with one-dimensional periodicity was made by laying a ZnO microrod of hexagonal cross-section onto silicon corrugated with 1-μm-wide channels, with a period of 2 μm. The ZnO rod forms a whispering-gallery mode resonator for the exciton–polaritons, subject to a periodic potential along the length of the wire due to the adjacent structured silicon. Photoluminescence was used to investigate the structure when optically pumped at room temperature. Long-range phase coherence was observed and for strong pumping the spatial period of the condensate is twice that of the superlattice period. The authors state that previous work using GaAs did not confirm the period-doubling feature of weak lasing and they suggest that ZnO may yield more robust weak lasing.
Rights and permissions
About this article
Cite this article
Pile, D. Weak lasing. Nature Photon 9, 283 (2015). https://doi.org/10.1038/nphoton.2015.72
Published:
Issue Date:
DOI: https://doi.org/10.1038/nphoton.2015.72
