Optical Properties of Rare Earth Doped Molybdenum Trioxide Thin Films

This study aims to investigate the optical properties of Dy-doped MoO3 thin films. MoO3 is a transition metal oxide with a band gap between 2.9 and 3.15 eV. The Dy-doped MoO3 films were grown using a pulsed laser deposition technique and were doped with 1% and 5% concentrations of dysprosium. Previous literature has reported that undoped MoO3 has a broad, main photoluminescence (PL) peak around 400 nm. However, the addition of Dy alters the emission spectra, which can be attributed to the crystalline electric field splitting of the f-orbitals of dysprosium. According to our preliminary results, there are at least three peaks in the PL emission spectra, with the main peak at 575 nm. Time-resolved PL (TRPL) was also performed on the 1% Dy-MoO3 sample. The lifetime decay of the 575 nm peak was measured at 4 K and 300 K, showing a decay of 129 ns at 4 K and 19 ns at 300 K. These preliminary results suggest promising optical properties for Dy-MoO3 thin films. Further studies are ongoing for the 5% Dy-MoO3 samples.