Photoluminescence modification by a high-order photonic band with abnormal dispersion in ZnO inverse opal
نویسندگان
چکیده
We measured the angleand polarization-resolved reflection and photoluminescence spectra of ZnO inverse opals. Significant enhancement of spontaneous emission is observed. The enhanced emission not only has good directionality but can also be linearly polarized. A detailed theoretical analysis and numerical simulation reveal that such enhancement is caused by the abnormal dispersion of a high-order photonic band. The frozen mode at a stationary inflection point of a dispersion curve can strongly modify the intensity, directionality, and polarization of spontaneous emission.
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