2005/01/29 by Shi-Jie Xu, Shijie Xu, Shi‐Jie Xiong +6
Chemistry · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Spectroscopy and Laser Applications #Spectroscopy and Quantum Chemical Studies #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0501723
12 pages, 4 figures
arxiv created 2005/01/29 · openalex publication_date 2005/01/29 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report a photoluminescence observation of robust excitonic polarons due to strong coupling of exciton and longitudinal optical (LO) phonon as well as Fano-type interference in high quality ZnO crystal. At low enough temperatures, the strong coupling of excitons and LO phonons leads to not only traditional Stokes lines (SLs) but also up to second-order anti-Stokes lines (ASLs) besides the zero-phonon line (ZPL). The SLs and ASLs are found to be not mirror symmetric with respect to the ZPL, strongly suggesting that they are from different coupling states of exciton and phonons. It is more interesting that a new group of peaks, including a ZPL and several SLs, are observed. The observations can be explained with a newly developed theory in which this group is attributed to the ground excitonic polaron state and the other group is from the excited polaron states with LO phonon components partially decaying into environal phonon modes. Besides these spectral features showing the quasiparticle properties of exciton-phonon coupling system, the first-order SL is found to exhibit characteristic Fano lineshape, caused by quantum interference between the LO components of excitonic polarons and the environal phonons. These findings lead to a new insight into fundamental effects of exciton-phonon interaction.