Scientists have demonstrated tunable red, green, and blue single-mode microlasers in optimized heterogeneously coupled cavities constructed with three spherical microcavities incorporated with different gain media. The microcavities with perfect circle boundaries and smooth surfaces were applied as high-quality WGM resonators.
Benefiting from the outstanding flexibilities, RGB lasing was obtained by doping the corresponding dyes into different WGM microcavities. Different color-emissive spherical cavities were integrated to form a heterogeneously coupled system using a strategy of nano architectonics. In such a heterogeneously coupled system, each microsphere serves as the laser source and the filter for the other resonator, enabling the output of single-mode laser from individual microcavities.
Furthermore, they fabricated a heterogeneously coupled system, which permits optical coupling between multiple resonators, thereby realizing tunable RGB single-mode microlasers. The results demonstrate a unique approach for the modulation of lasing modes in heterogeneously coupled cavities and shed new light on the generation of microlasers capable of emitting over the full visible spectrum with high spectral purity for integrated optoelectronic systems.
Benefiting from the doping flexibility of organic materials, the color of the single-mode lasers output from the heterogeneously coupled structure can be freely designed by doping different gain media into the spherical microcavities.
Related Content: Laser Processing Method For Efficient Optoelectronics