Fig. 1. Synthesis, morphology, and characterization of CsPbBr₃ nanorods. (a) Flow chart of sample preparation; (b) TEM image of nanorods (insert shows high-resolution TEM of nanorods); (c) size distribution of CsPbBr₃ nanorods; (d) XRD spectrum of CsPbBr₃ nanorods

Fig. 2. Optical properties of CsPbBr₃ nanorods. (a) UV-VIS absorption and PL spectra; (b) pseudo-color map of temperature dependent PL spectra; (c) FWHM and PL peak energy as a function of temperature; (d) normalized integrated PL intensity as a function of temperature

Fig. 3. Nonlinear optical properties of perovskite nanorods. (a) ASE intensity of CsPbBr₃ perovskite nanorods as a function of stripe length, the insert illustrates schematic diagram of VLS measurement; (b) PL spectra of CsPbBr₃ nanorod under different pumping densities at room temperature; (c) integrated PL intensity and FWHM as a function of pump density

Fig. 4. Stability test of materials. (a) ASE stability of the nanorods material; (b) comparison between PL intensity stability of the CsPbBr₃ perovskite nanorods and nanocrystal after aging experiment (under 85%RH at 85 ℃)