Broadband Tunability of Third Harmonic Upconversion in Pyridinium Lead Halides

Abstract

Lower dimensional lead halide perovskites have demonstrated highly enhanced nonlinear optical properties due to strong quantum and dielectric confinement. Broadband wavelength tunability of efficient nonlinear optical performance is a critical challenge in futuristic applications. The structural versatility of the perovskites provides a number of parameters for achieving this functionality. Varying the halide composition can tune the bandgap of lead halide perovskites, which can be employed to achieve the wavelength tunability of the nonlinear optical response. We varied the halide composition of the 1D pyridinium lead halide system to realize broadband tunability for the third harmonic upconversion process. An efficient but complex third harmonic response was observed from these systems, which was affected by the induced lattice strain due to the mixed halide composition. We achieved efficient third harmonic generation over a wide wavelength (400–550 nm) range by tuning the halide composition. Remarkable optical stability, efficient third-order susceptibility, and broadband wavelength tunability make these perovskite systems attractive propositions for real applications