Laser Systems and Networks with Organic Nanowires and Nanofibers

Abstract

The potentialities of miniaturized laser sources are still far from being fully developed. Unprecedented opportunities are generated in this field by organic nanowires and nanofibers, which can be used as building blocks of micro‐ and nanolasers in which they combine optical gain, waveguiding, and very high versatility to create nanophotonic networks. The progress in laser devices and network architectures based on optically pumped organic light‐emitting nanowires and nanofibers is here presented, with emphasis on developed active materials, fabrication technologies, lasing mechanisms, and cavity geometries, and on achieved device performance in terms of spectral tunability, excitation threshold, and resonator quality factors. Recent examples of optical coupling of different miniaturized lasers, of their application in optical sensing, and of network lasers are presented. Future directions for research are also outlined, which include the exploration of new classes of active organic or hybrid materials within nanowires, the more in‐depth characterization of the fundamental properties of these lasers, and the use of topologically defined organic nanophotonics in network science, computing, and diagnostics.

Deep‐Blue Thiophene‐Based Steric Oligomers as a Low‐Threshold Laser Gain and Host Material

“…When the optical gain property was further characterized, we observed that the neat film exhibited a remarkably low threshold , 6.0 µJ cm −2 ) with an exceptional narrow FWHM (2.6 nm) under the vacuum condition (10 −4 Pa), which is similar to the previously reported organic lasers (Figure 1b). [ 12,57–65 ] This deep‐blue ASE emission exhibited a peak at 427 nm, belonging to the 0–1 transition, and the emission can be achieved repeatedly with films spin coated from the toluene solution of MC8‐Th (10 mg mL −1 ). Furthermore, after dispersing MC8‐Th (10 wt%) into inert PS matrix, we achieved a kind of deep‐blue random laser emission (under vacuum condition) with a lower of 4.1 µJ cm −2 (Figure 1c).…”

“…Besides, the film morphology investigated using fluorescence microscope (FLM) and atomic force microscope (AFM) (Figure S7, Supporting Information) showed that there are a range of nanoparticles distributed in the neat film, which may act as the optical resonant cavity for organic lasers. [ 12,57–59 ] In contrast, the PS‐blend film exhibited homogeneous film morphology reflected by the FLM image and AFM height image, demonstrating that encapsulating the novel material in inert polymer matrix is favorable for improving the emission efficiency and optimizing morphology of the film.…”

Thermally Activated Delayed Fluorescent Gain Materials: Harvesting Triplet Excitons for Lasing

“…[46,47] One-dimensional microcrystals that can function as Fabry-Pérot (FP) cavities can be formed via a simple solution self-assembly method (Figure 5a). [66,68] Lasing emissions with different colors were realized with low thresholds (Figure 5b). For the microrods of compound 4a, the Q factor was estimated to be as high as ≈1313 at a wavelength of 525 nm.…”

Low Threshold Microlasers Based on Organic-Conjugated Polymers

“…Most of one-dimensional microscopic wires/fibers present typical Fabry–Pérot feedback features with the body part of wire showing good waveguiding capacity and the tip parts acting as mirrors ( Matino et al, 2019 ). Conjugated polymers with high gain properties can be fabricated to micro/nanowires via facile techniques such as prepatterned templating, micromolding, and self-assembly.…”