2025/10/08 by Anand Dewansingh, Dewansingh, Anand, Deaton, Abigail +6
Chemistry · Engineering · #FOS: Physical sciences #Laser Design and Applications #Optics (physics.optics) #Solid State Laser Technologies #Spectroscopy and Laser Applications
paper · pdf · doi:10.48550/arxiv.2510.07188
openalex publication_date 2025/10/08 · openalex created_date 2025/10/18 · openalex updated_date 2026/07/30
A liquid-core (LiCo) dye laser was demonstrated using Rhodamine B (RhB) dissolved in glycerol as the gain medium and fluorinated ethylene propylene (FEP) tubing as the waveguide. Photoluminescence and amplified spontaneous emission (ASE) studies identified optimal RhB concentrations of 0.1 wt.% and 0.3 wt.% for low-threshold laser operation. Laser emission was achieved in LiCo rods with 1/16 inch and 1/32 inch inner diameter FEP tubing, with narrower tubing providing enhanced mode confinement and spectral narrowing. The addition of cavity mirrors improved emission coherence, revealing a distinct laser mode at low pump energies with mode spacing inconsistent with a simple Fabry-Pérot cavity, indicating complex mode coupling and internal reflections. Limitations include spectral broadening and scattering-induced parasitic feedback, which suggest avenues for further optimization in waveguide materials and output coupling.