Pure Metal–Organic Framework Microlasers with Controlled Cavity Shapes

Abstract

Metal−organic frameworks (MOFs) are an emerging kind of laser material, yet they remain a challenge in the controlled fabrication of crystal nanostructures with desired morphology for tuning their optical microcavities. Herein, the shape-engineering of pure MOF microlasers was demonstrated based on the coordination-mode-tailored method. The one-dimensional (1D) microwires and 2D microplates were selectively fabricated through changing the HCl concentration to tailor the coordination modes. Both the single-crystalline microwires and microplates with strong optical confinement functioned as low-threshold MOF microlasers. Moreover, distinct lasing behaviors of 1D and 2D MOF microcrystals confirm a typical shape-dependent microcavity effect: 1D microwires serve as Fabry−Peŕot (FP) resonators, and 2D microplates lead to the whispering-gallerymode (WGM) microcavities. These results provide a special pathway for the exploitation of MOF-based micro/nanolasers with on-demand functions.

Hydrogen-Bonded Organic Framework Microlasers with Conformation-Induced Color-Tunable Output

“…The values of the HOF microwire length and the mode spacing (Δλ) agreed with the Fabry−Peŕot (FP) theory equation λ 2 /Δλ = 2 nL, where λ represents the wavelength and n represents the group refractive index, indicating that the optical-mode modulation was induced by the FP-type resonance (Figure 4C). 51 The linear relationship between λ 2 /2Δλ and the L of the nanowires further confirms that the PL modulation results from the axial FP-type cavity resonance. Therefore, these HOF microwires can give rise to the FP optical feedback, in which light can reflect from the crystalline end facets of the microwires and propagate back through the gain medium.…”

Halide Perovskite Lateral Heterostructures for Energy Routing Based Photonic Applications

“…In addition, thanks to the atomically flat surface, these heterostructures could exhibit efficient waveguiding and/or photon recycling behavior. [ 23 ] This can be confirmed by partially exciting the microplate at the center via a focused laser beam (wavelength: 405 nm) using far‐field microscopy (Figure 2b). The bright green emission from the four edges (Figure 2c) together with the appearance of dark color out of the excitation spot indicates the efficient waveguiding and photon recycling property of the perovskite heterostructure.…”

Recent Progress in Luminous Particle‐Encapsulated Host–Guest Metal‐Organic Frameworks for Optical Applications

“…[259] Recently, even pure MOFs microlasers with controlled cavity shapes have been achieved. [260] It follows that the laser wavelength and excitation photons can be further extended based on the adjustable energy levels of different guest molecules restrained in diverse MOFs.…”