Single Longitudinal Mode Optofluidic Microring Laser Based on a Hollow-Core Microstructured Optical Fiber

A single longitudinal mode microring dye laser based on a simplified hollow-core microstructured optical fiber (SHMOF) is proposed and demonstrated. The dye laser uses a submicron thickness silica microring embedded in the SHMOF as resonator and has the characteristic of a low threshold of 664 nJ/mm
²
. The factors that influence the single longitudinal mode excitation are discussed and the possible operation principle is analyzed. Meanwhile, the single longitudinal mode emissions at several different wavelengths are realized by using different dyes as gain medium, which indicates that the lasing wavelength of the laser is scalable. Time domain characteristics of the lasing are also measured and they are synchronous with the lateral pumping laser. The attractive possibility of developing microfluidic single longitudinal mode dye laser within the SHMOF presents opportunities for integrated optics applications and biomedical analysis with high sensitivity.