Random laser from engineered nanostructures obtained by surface tension driven lithography

TL;DR

This paper demonstrates a method to create shape-controlled organic random lasers using surface tension driven lithography to pattern molecular self-assembly, enabling tailored emission properties without external resonators.

Contribution

It introduces a novel surface tension driven lithography technique for patterning organic materials into nano-aggregates that serve as scattering centers for random laser emission.

Findings

Controlled supramolecular nano-aggregates act as scattering centers.

Patterned shapes influence the emission coherence.

Surface tension driven lithography enables shape and efficiency control.

Abstract

The random laser emission from the functionalized thienyl-S,S-dioxide quinquethiophene (T5OCx) in confined patterns with different shapes is demonstrated. Functional patterning of the light emitter organic material in well defined features is obtained by spontaneous molecular self-assembly guided by surface tension driven (STD) lithography. Such controlled supramolecular nano-aggregates act as scattering centers allowing the fabrication of one-component organic lasers with no external resonator and with desired shape and efficiency. Atomic force microscopy shows that different geometric pattern with different supramolecular organization obtained by the lithographic process tailors the coherent emission properties by controlling the distribution and the size of the random scatterers.