Unidirectional Lasing Emissions from CH₃NH₃PbBr₃ Perovskite Microdisks

Very recently, perovskite based microdisk lasers have attracted considerable research attention. However, most of the researches are focused on the lasing spectra in bottom-up synthesized microdisks with regular shapes. The directionality, which is also essential for practical applications, has not been explored. Here we demonstrate unidirectional lasing emissions from perovskite microdisks for the first time. We synthesized the rectangle-shaped microdisks connected with straight waveguides and studied the lasing characteristics, where unidirectional emissions along the waveguides have been observed. Numerical calculations reveal that the unidirectional emissions are formed by the breaking of total internal reflections at the joints between waveguides and microdisks. Since waveguides are compatible with other photonic elements, we believe that our finding will be essential for the applications of perovskite microdisks in integrated photonic circuits and networks.