Palestrante
Descrição
The interaction of light with organic gain materials in resonant structures provides a mechanism to enhance the sensing capabilities for detection of chemical species, including gases and biomolecules. For any laser to work a set of parameters and conditions must be tuned: excitation threshold, cavity losses, photophysical absorption-emission dynamics, medium refractive index, and matching conditions of feedback in resonant structures. If any of these parameters can be made dependent on the concentration of a desired analyte, we may be able to obtain a very sensitive sensor device. The enhancement of sensing capabilities in laser-based devices has been reported in the literature, for detection of traces of hazardous gases (1) and biomolecules. (2) Organic lasers do not compete with inorganic III-V lasers but organic gain materials are advantageous owing to their broad absorption and emission in the UV-visible spectra. Furthermore, with these organic materials simple fabrication methods can be used with solution processing, and it is possible to tailor the chemical structure for special electronic photophysical properties. Indeed, thin film lasers have been obtained with various resonator architectures and emission wavelength tunability in the visible spectra. (3) Research on electrically-pumped organic laser diodes led to low-threshold devices, possibly pumped by commercial light-emitting diodes (LEDs) under pulsed operation (1), and techniques that turn possible organic lasing in the quasi-Continuous Wave (qCW) regime. (3) The electrically pumped organic laser remains a challenge. Herein, we aim to develop an organic thin film laser pumped by a compact light source such as an LED or laser diode, in addition to demonstrating lab-on-chip (LOC) devices for chemical sensing. The organic laser sensor may be capable to detect traces of toxic gases for environmental monitoring at room temperature and normal ambient conditions.
Referências
1 WANG, Y. et al. LED pumped polymer laser sensor for explosives. Laser and Photonics Reviews, v. 7, n. 6, p. L71-L76, 1 Nov. 2013.
2 MCCONNELL, G. et al. Organic semiconductor laser platform for the detection of DNA by AgNP plasmonic enhancement. Langmuir, v. 34, n. 49, p. 14766-14773, Dec. 2018.
3 CHÉNAIS, S.; FORGET, S. Recent advances in solid-state organic lasers. Polymer International, v. 61, n. 3, p. 390-406, Mar. 2012.
| Apresentação do trabalho acadêmico para o público geral | Sim |
|---|---|
| Subárea | Física de Materiais |
