UV–VIS absorption and NIR‐stimulated emission of Nd3+: PVA films

Neodymium-doped polyvinyl alcohol films were prepared and the optical properties of the films were investigated. By applying Judd–Ofelt theory, the Ω parameters were obtained from the absorption spectrum. Various radiative parameters like transition probability for each level (AJ), total transition probability (AT), branching ratio (βR), radiative lifetime (τrad), and absorption cross-section (σA) were calculated. The theoretically obtained branching ratio and integrated absorption cross-section are found to be greater for the transition 4F3/2 4I11/2. From the emission spectrum peaked at 1064-nm stimulated emission cross-section (σE), the line width (Δλeff) is calculated to be 6.21 × 10−21 cm2 and 41 nm, respectively. Further the variation of the optical gain with the length of the film was studied and the slope efficiency (η = 8.5%) was determined from laser measurements. These results clearly support the potentiality of the Nd3+: polyvinyl alcohol films in realizing optical amplification and stimulated emission. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009