Random laser performance by magneto-plasmonic nanoparticles

This work aims to control the random laser performance using magnetic-plasmonic nanoparticles including Fe3O4 and Au nanoparticles mixed with the active laser media R6G dye. For this purpose, Au nanoparticles were produced via the electrical exploding wire method and mixed with the Fe3O4 nanoparticles in the dye medium. After characterizing the samples through the transmission electron microscopy and the florescence spectra in the visible region, they were pumped by the second harmonic generation of the Nd: YAG laser where the random lasing action was detected by a spectrometer. These measurements were performed with and without external magnetic field at 35 mT. The results revealed a nice full width at half maximum of random laser efficiency in the samples exposed to the external magnetic field. In addition, using the external magnetic field, the coherency percentage of the random lasing action diminished because of the fixed direction of the magnetic field which was collinear to the cell direction that can affect the coherency loop due to nanoparticles' arrangement direction in the dye medium.