Fifth-order nonlinear optical response of Alq(3) thin films

Saleh, Ahmad; Li, Weiwei; ALQahtani, Hadi; Neuhaus, Marcel; Alshehri, Ali; Bergues, Boris; Alharbi, Meshaal; Kling, Matthias F.; Azzeer, Abdallah M.; Wang, Zilong und Alharbi, Abdullah F. (2022): Fifth-order nonlinear optical response of Alq(3) thin films. In: Results in Physics, Bd. 37, 105513

Abstract

The fifth-order optical nonlinearity of Tris-(8-hydroxyquinoline) aluminium (Alq3) thin films deposited on quartz substrates when exposed to an intense laser excitation of mid-infrared femtosecond pulses is investigated. This property was examined by generating the fifth-harmonic frequency of the driving field whose signal strength as a function of laser intensity is well described by a power-law scaling. The perturbative nature of the underlying mechanism enabled the linking of the process directly to the fifth-order nonlinear optical susceptibility chi((5)). We also utilized the open-aperture z-scan for studying the nonlinear absorption aspect of the third-order nonlinear optical properties of the sample. It was found that Alq(3) thin-films inherit the same saturable absorption character reported in Alq(3) solutions under continuous laser excitation in the visible range, with a comparable value of the nonlinear absorption coefficient beta(eff) (in the order of 10(-2) cm/W).

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2211-3797
• Sprache: Englisch