Stimulated emission from aluminium anode oxide films doped with rhodamine 6G

The spectral and luminescent properties of the rhodamine 6G dye in a porous matrix of aluminium anode oxide are studied. The films with a highly-ordered porous structure are produced using the method of two-stage anodic oxidation. By means of raster electron microscopy it is found that the diameter of the pores amounts to nearly 50 nm and the separation between the adjacent channels is almost 105 nm. The thickness of the films is equal to 55 μm, and the specific surface area measured using the method of nitrogen capillary condensation is 15.3 m² g^-1. Fluorescence and absorption spectra of rhodamine 6G molecules injected into the pores of the aluminium anode oxide are measured. It is found that under the excitation of samples with the surface dye concentration 0.3 × 10¹⁴ molecules m^-2 by the second harmonic of the Nd : YAG laser in the longitudinal scheme with the pumping intensity 0.4 MW cm^-2, a narrow band of stimulated emission with the intensity maximum at the wavelength 572 nm appears against the background of the laser-induced fluorescence spectrum. A further increase in the pumping radiation intensity leads to the narrowing of the stimulated emission band and an increase in its intensity. The obtained results demonstrate the potential possibility of using the porous films of aluminium anode oxide, doped with laser dyes, in developing active elements for quantum electronics.