UV–VIS absorption and NIR‐stimulated emission of Nd 3+ : 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 ( A J ), total transition probability ( A T ), branching ratio (β R ), radiative lifetime (τ rad ), and absorption cross‐section (σ A ) were calculated. The theoretically obtained branching ratio and integrated absorption cross‐section are found to be greater for the transition 4 F 3/2 → 4 I 11/2 . From the emission spectrum peaked at 1064‐nm stimulated emission cross‐section (σ E ), the line width (Δλ eff ) is calculated to be 6.21 × 10 −21 cm 2 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 Nd 3+ : polyvinyl alcohol films in realizing optical amplification and stimulated emission. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009