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

Abstract

Neodymium-doped polyvinyl alcohol films were prepared and the optical properties of the films were investigated. By applying Judd-Ofelt theory, the X 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 (b R ), radiative lifetime (s rad ), and absorption cross-section (r 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 (r E ), the line width (Dk eff ) is calculated to be 6.21 Â 10 À21 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 (g ¼ 8.5%) was determined from laser measurements. These results clearly support the potentiality of the Nd 3þ : polyvinyl alcohol films in realizing optical amplification and stimulated emission.

Freestanding Ag2S/CuS PVA films with improved dielectric properties for organic electronics

“…FTIR is used to testify the interaction of PVA with the surface of silica‐capped nanofillers. As shown in Figure , PVA has two characteristic peaks at around 2900 and 1700 cm −1 which are associated with vibration modes of CH 2 and CO groups . The CO groups are present in unhydrolysed PVA, containing OH vibrations.…”

“…The frequency dependence of ac‐conductivity and dielectric constant of the PVA–PbS nanocomposite and p‐type (PVA/CuI) nanocomposite polymer has been carried out earlier with the aid of complex/dielectric spectroscopic investigations. Silica glasses doped with varying contents of CdSe nanocrystallites are prepared by the sol–gel exhibited the conductivity values of the order of 10 −5 −10 −7 S/cm . Moreover, superior dielectric behavior of the multiwalled carbon nanotube‐CdS/polyvinyl alcohol (MWCNT‐CdS/PVA) composites over MWCNT and PVA host matrices has been demonstrated .…”

Properties of poly(vinyl alcohol)–borax gel doped with neodymium and praseodymium

“…Figure 5 shows spectra from the gels with varying Nd:Pr ratios. The undoped sample shows a weak band at 280 nm due to the carbonyl groups associated with ethylene unsaturation which indicates the presence of conjugated polyene double bonds (Adiyodi et al 2009). This weak band reduces in intensity as the relative concentration of Pr 3+ increases in the gels.…”

Heteronuclear Bimetallic Complexes with 3d and 4f Elements

“…52-54 mol dm −1 cm −1 , corresponding to d → d transitions. In the spectrum of 1-Nd, sharp bands at 525, 581, 736, 797, and 870 nm can be identified arising from the weak, Laporte-forbidden, f -f transitions, with the most intense of these being the 4 I 9/2 → 4 G 5/2 transition at 581 nm [26].…”