Photonic Diffusion through Dynamic Gain Gratings

摘要

Three pairs of the 2nd harmonic of a telescopic resonator Nd: YAG laser pumped a typical Shank type dye cell consisting of solution of Rh6G in ethanol. Dichroic mirrors were used as beam splitters to produce three pairs of excitation beams. A cylindrical telescope was inserted before the last beam splitter to focus the beams on to the dye. Three distinct gain gratings were produced corresponding to three pairs main beams. These gratings were superimposed upon each other within +-1.5~r in the dye cell. These three gratings of different periodicities were individually able to cause typical distributed feedback laser action. Operating one and blocking the others at a time confirmed that the individual operation of these distributed feedback dye lasers (DFDLs) resulted in oscillation at 560, 580 and 600 nm wavelengths respectively. Simultaneous operation of three DFDLs resulted in total 9 lines with light yellow color outlook shifting to pink by varying the intensities of the excitation beams. The output color varied from dark pink to lightly yellow by adjusting the intensities and angles of the excitation beams. Results show, if dye solution supports, then it is possible to design a photon diffused white light distributed feedback dye laser.