Department of Molecular Biology and GeneticsDepartment of Electrical and Electronics Engineering2024-11-0920170003-695110.1063/1.50072432-s2.0-85037709258https://hdl.handle.net/20.500.14288/3578Here, we report a single transverse mode distributed feedback (DFB) protein laser. The gain medium that is composed of enhanced green fluorescent protein in a silk fibroin matrix yields a waveguiding gain layer on a DFB resonator. The thin TiO2 layer on the quartz grating improves optical feedback due to the increased effective refractive index. The protein laser shows a single transverse mode lasing at the wavelength of 520 nm with the threshold level of 92.1 mu J/mm(2).pdfPhysics, appliedJournal Article1077-3118https://doi.org/10.1063/1.5007243418349100003Q2NOIR01508