Researchers at NTU, lead by Assoc. Prof. Wang Hong, recently demonstrated high light extraction efficiency of perovskite photonic crystals fabricated by delicate electron-beam lithography.
The perovskite photonic crystals exhibit both emission rate inhibition and light energy redistribution simultaneously. They observed 7.9-fold reduction of spontaneous emission rate with a slower decay in perovskite photonic crystals due to photonic bandgap effect (PBG).
They also reported 23.5-fold emission intensity enhancement as results of light energy redistribution from 2D guided modes to vertical direction in perovskite photonic crystals thin films, indicating a high intrinsic light extraction efficiency.
This observation is the second largest extraction efficiency with two-dimensional photonic crystals in comparison with that of 500 folds in Silicon. These findings offer a new promising approach in various applications for perovskite, including solar cell, displays and photovoltaics.