RAMAN SPECTROSCOPY OF Ho-DOPED LITHIUM NIOBATE THIN FILMS

Abstract

Ho-doped lithium niobate (LN:Ho³⁺) thin films on sapphire substrates employing the Sol-Gel technique were synthesized. The Raman scattering mapping of the obtained LN:Ho³⁺ thin films were meticulously obtained through laser excitation at both 785 nm and 532 nm wavelengths. For both cases, a homogeneous distribution of the crystal structure on the surface of the substrate were confirmed. In contrast, the case of 785 nm laser excitation, during the pumping of the films by the laser at 532 nm multiple additional forbidden Raman lines were present, which were attributed to luminescence of impurity ions.