▎ 摘 要
This paper presents a simple and cost-effective method to obtain directionality and enhancement of intensity in random lasers (RLs). For this purpose, a thin liquid dye layer containing graphene quantum dots (GQDs) is sandwiched between two microscope glass slides. GQDs provide optical feedback for resonant RLemission via multiple scattering. The resonant RLemission from GQDs doped dye solution is coupled into microscope glass slides providing a waveguide structure. Two bright spots are observed along edge sides of microscope glass slides. Resonant RL emission also occurs in front side of the microscope glass slides which is not directional and significantly weaker than the emission in the edge side. Furthermore, it is demonstrated when a dye solution without any scattering particles is sandwiched between two microscope glass slides, two emission spots with high intensity are seen along the edge side whose spectrum includes a broad and intensive single peak.