Zhang, QingLi, GuangyuanLiu, XinfengQian, FangLi, YatSum, Tze ChienLieber, CharlesXiong, Qihua2014-10-012014Zhang, Qing, Guangyuan Li, Xinfeng Liu, Fang Qian, Yat Li, Tze Chien Sum, Charles M. Lieber, and Qihua Xiong. 2014. “A Room Temperature Low-Threshold Ultraviolet Plasmonic Nanolaser.” Nature Communications 5: 4953.2041-1723http://nrs.harvard.edu/urn-3:HUL.InstRepos:12991706Constrained by large ohmic and radiation losses, plasmonic nanolasers operated at visible regime are usually achieved either with a high threshold (102–104 MW cm−2) or at cryogenic temperatures (4–120 K). Particularly, the bending-back effect of surface plasmon (SP) dispersion at high energy makes the SP lasing below 450 nm more challenging. Here we demonstrate the first strong room temperature ultraviolet (~370 nm) SP polariton laser with an extremely low threshold (~3.5 MW cm−2). We find that a closed-contact planar semiconductor–insulator–metal interface greatly lessens the scattering loss, and more importantly, efficiently promotes the exciton–SP energy transfer thus furnishes adequate optical gain to compensate the loss. An excitation polarization-dependent lasing action is observed and interpreted with a microscopic energy-transfer process from excitons to SPs. Our work advances the fundamental understanding of hybrid plasmonic waveguide laser and provides a solution of realizing room temperature UV nanolasers for biological applications and information technologies.en-USPhysical sciencesOptical physicsJournal Article2014-08-28Qing Zhang, Guangyuan Li, Xinfeng Liu, Fang Qian, Yat Li, Tze Chien Sum, Charles M. Lieber and Qihua Xiong2015-03-2410.1038/ncomms5953