Optical signatures of exciton-polariton condensation in single ZnO microrod
Ya-Tang Chuang1*, Tzu-Yang Chao1, Kai-Hsiang Lin1, Hsu-Cheng Hsu1,2
1Department of Photonics, National Cheng Kung University, Tainan, Taiwan
2Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan
* presenting author:莊雅棠, email:lily061007@gmail.com
Exciton-polariton, which is a quasi-particle formed by strong coupling between exciton and cavity mode, has attracted much attention due to its excellent optical properties. Here we report the experimental results of the whispering-gallery-mode polariton lasing in one dimensional ZnO microrod. The luminescence properties of single ZnO microrod were investigated by angle-resolved micro-photoluminescence spectroscopy at room temperature. With the excitation power increase, the peak position of emission shows tendency towards a blueshift, indicates that the strong interaction of the polaritons. Above threshold, the exciton-polariton condensation can be observed in dispersion spectra at k//=0. The spontaneous buildup of spatial coherence in condensate state was obtained by Young’s double-slit experiment.
This research is financially supported by the Ministry of Science and Technology of Taiwan under grant NSC-102-2112-M-006-012-MY3 and the Aim for the Top University Project of the Ministry of Education.

Keywords: ZnO , microrod, polariton, condensation