Fig. 1. Nucleation rate and growth rate varying with temperature^[36]

Fig. 2. Optical images of femtosecond laser-induced dots (after annealing) formed at different laser power densities and exposure time^[44]. (a) Natural light; (b) 365 nm ultraviolet light (after annealing); (c) transmission electron microscope image; (d) high resolution transmission electron microscope image; (e) size distribution of nanocrystals

Fig. 3. Fluorescence micrographs of lines written by femtosecond laser with pulse energy of 12 μJ, scanning rate of 5 μm/s, and repetition rate in range of 25-200 kHz^[47]. (a) Fluorescence photo of written lines without thermal treatment under 365 nm light illumination; (b) photoluminescence spectra of lines written by femtosecond laser in Fig. 3(a); (c) fluorescence photo of written lines under 365 nm light illumination after thermal treatment at 400 ℃ for 5 h; (d) photoluminescence spectra of lines written by femtosecond laser in Fig. 3(c)

Fig. 4. Photoluminescence spectra and luminescence intensity statistics of laser-induced CsPbI₃ dots under different repetition rates and pulse widths^[48]. (a) Photoluminescence spectra of CsPbI₃ dots excited by 405 nm ultraviolet light with laser energy density of 6.4 J·cm^-2, pulse width of 230 fs, exposure time of 800 ms and repetition rate range of 75-200 kHz; (b) photoluminescence spectra of CsPbI₃ dots excited by 405 nm ultraviolet light with laser energy density of 25.6 J·cm^-2, pulse width of 230 fs, exposure time of 800 ms and repetition rate range of 30-200 kHz; (c) full width at half maximum of photoluminescence spectrum varying with repetition frequency in Fig. 4(b); (d) luminescence intensity statistics of laser-induced CsPbI₃ dots under different repetition rates and pulse widths; (e) luminescence intensity statistics of CsPbI₃ dots excited by 405 nm ultraviolet light with laser energy density of 19.2 J·cm^-2, repetition rate of 100 kHz, and pulse width range of 230 fs-5 ps

Fig. 5. Photoluminescence spectra of nanocrystals and corresponding photoluminescence photos^[49]. (a) Photoluminescence spectra and corresponding photoluminescence photos of precipitated nanocrystals obtained by ultrafast laser direct writing in Cl-Br-I co-doped perovskite glass; (b) photoluminescence spectra and corresponding photoluminescence photos of precipitated nanocrystals obtained by laser direct writing under different irradiation time

Fig. 6. Principle schematic diagram of ultrafast laser-induced liquid nanophase separation and precipitation of CsPb(Br_1-xI_x)₃ nanocrystals in Br-I co-doped glass^[49]

Fig. 7. Encrypted display of nanocrystal patterns in glass and optical storage demonstration. (a) Demonstration of CsPb(Cl/Br)₃ nanocrystal erasable pattern in glass for information encryption and decryption^[45]; (b) laser-induced nanocrystal optical storage demonstration^[49]; (c) (d) laser direct writing color nanocrystal luminescence patterns^[49]

Fig. 8. Application of nanocrystal patterned devices^[49]. (a) Photographs of micro-LED devices; (b) three-dimensional holographic display