Erbium-doped glass nanoparticle embedded polymer thin films using femtosecond pulsed laser deposition

Polymer materials doped with rare-earth ions are promising candidates for the formation of low-cost integrated optical amplifiers. However, there are significant technical challenges associated with the integration of these dissimilar materials and the formation of high-quality Er-doped polymer films. In this paper, therefore, we present for the first time the fabrication of polymer thin layers modified with erbium-doped sodium zinc tellurite (Er- TZN) glass nanoparticles (NPs) using femtosecond (fs) pulsed laser deposition (PLD) and the characterisation of their basic properties. The surface morphology and the compositional and structural characteristics of the samples produced with this method are evaluated using scanning and transmission electron microscopy (SEM and TEM) and X-ray diffraction (XRD), while photoluminescence (PL) measurements are carried out at room temperature under a 980 nm laser diode excitation. The studies indicate that the Er-doped TZN NPs are successfully integrated in the polymer layers. The obtained average NP size is measured to be in the range of 12 to 21 nm depending on the fabrication parameters, while broad PL emission at 1534 nm that corresponds to the ⁴I_13/2 →⁴I_15/2 transition of Er³⁺ is observed from the samples. The full-width at half-maximum (FWHM) of the PL spectra is found to be ~39 nm while the fluorescence lifetime is measured to be in the range of 3.52 to 4.18 ms. The obtained results clearly demonstrate the potential to efficiently dope polymer layers with glass NPs using fs-PLD and is a first step towards the successful formation of hybrid polymer-glass waveguide amplifiers.