Several Orders-of-Magnitude Enhancement of Multiphoton Absorption Property for CsPbX₃ Perovskite Quantum Dots by Manipulating Halide Stoichiometry

Abstract

Two-photon absorption (2PA) and three-photon absorption (3PA) processes feature many technological applications for fluorescence microscopy, photodynamic therapy, optical data storage, and so on, Herein, we reveal that the giant 2PA and 3PA properties for all-inorganic CsPbX3 (X = Cl, Br, I, and mixed Cl/Br and Br/I) perovskite quantum dots (PQDs) can be enhanced several orders of magnitude, respectively, by simply changing the halide stoichiometry at the X site. Notably, reported data show excellent 2PA and 3PA properties for CsPbI3 (σ2 ∼ 2.1 × 106 GM and σ3 ∼ 1.1 × 10–73 cm8 s3/photon3), which is 2–4 orders of magnitude higher than those of conventional red-emitting QDs and 5–7 orders of magnitude higher than well documented organic molecules. Experimental results show multiphoton absorption (MPA) cross sections can be adjusted 2–3 orders of magnitude by band gap engineering in a predictable manner, via increasing the Pauling electronegativity of the halide. Two-photon luminescence imaging data show that PQDs can be used for very good multiphoton imaging applications. Importantly, reported results provide a new strategy for manipulating MPA properties by halide composition engineering which will be instrumental in the design of next-generation technological devices.

The Two-Photon Absorption Cross-Section Studies of CsPbX3 (X = I, Br, Cl) Nanocrystals

“…Recalculated values of the cross-section for two-photon absorption referred to a whole nanoparticle were on the order of 10 4 –10 5 GM. These are in very good agreement with the report of σ 2 for CsPbX 3 NCs with a mixed halide content by Pramanik et al [ 19 ]. To the best of our knowledge most other studies have focused on CsPbBr 3 NPs as the most stable ones and the presented values are ~10 5 GM [ 15 , 16 , 17 , 18 ].…”

“…There have been a few reports on the measurements of the magnitude of the two-photon absorption cross-section for perovskite NCs, which showed results from 10 4 up to 10 6 GM, proving that CsPbX 3 NCs can be very good two-photon absorbers [ 14 , 15 , 16 , 17 , 18 , 19 ]. While those results sound promising there is a need for more systematic studies of the third-order nonlinear optical properties of such systems, which would use proven techniques and procedures to obtain results that can be compared with those for other materials, including such disparate systems as semiconductors, dyes, polymers and dendrimers, or hybrid systems.…”

Water Triggered Synthesis of Highly Stable and Biocompatible 1D Nanowire, 2D Nanoplatelet, and 3D Nanocube CsPbBr3 Perovskites for Multicolor Two-Photon Cell Imaging

“… 45 − 54 Experimental details have been reported before and are discussed in the Supporting Information . 47 , 55 , 58 − 60 , 68 − 71 In brief, for the measurement, we used an 80 MHz Ti-sapphire laser as an excitation source with 100 fs pulse width. 47 , 55 , 58 − 60 We used an optical parametric amplifier to generate 800 nm excitation wavelength.…”

“… 47 , 55 , 58 − 60 , 68 − 71 In brief, for the measurement, we used an 80 MHz Ti-sapphire laser as an excitation source with 100 fs pulse width. 47 , 55 , 58 − 60 We used an optical parametric amplifier to generate 800 nm excitation wavelength. 3 , 47 , 55 , 58 , 60 The laser beam was focused down to a radius of ∼30 μm on the sample.…”

Optical studies of semiconductor perovskite nanocrystals for classical optoelectronic applications and quantum information technologies: a review

“…The two-photon absorption cross sections have been estimated for ensemble perovskite NCs by means of collection efficiency, 108,160 Z-scan, 107,109,[160][161][162] and TA 163 measurements.…”