Magneto-plasmonic-induced random laser in two-dimensional FeB square array

Abstract

This work aims to enhance the lasing parameters of a random laser using magneto-plasmonic FeB@Au as scattering points. Two-dimensional FeB square arrays are covered by thin films of Rhodamine 6 G from the bottom and top, respectively. For this purpose, two-dimensional structures were fabricated using the soft lithography method onto the polydimethylsiloxane (PDMS) substrate and deposited with a 35 nm thick gold layer using a sputtering machine, followed by a FeB (iron boride) thin layer using the radio frequency (RF) sputtering machine method. Finally, the samples were coated by rhodamine 6 G dye. The samples were pumped via the second harmonic generation of the Nd:YAG laser under an external magnetic field set to 50 mT, and the random lasing action was measured using a spectrometer. Our results indicated a better ability to achieve random lasing under the external magnetic field. The output emission spectra increased with a decreased laser threshold from 0.66 mJ to 0.35 mJ, and the full width at half maximum (FWHM) decreased from 7.8 nm to 4 nm.