Figure 6
(a) Single-mode lasing spectrum of triple microrings laser with radii of 30, 34, and 35 µm for different pump energies, the exciting laser wavelength is achieved at 612 nm with 0.6 nm FWHM (spectrometer resolution is 0.5 nm) and is highly stable with increasing pump energy. (b) Improved corresponding SMSR for triple mutual microrings laser that is more than 20 dB. (c) The normalized output emission intensity of triple microrings laser compared to double microring resonators as a function of pump energy. The solid black line shows the triple microrings lasing threshold of∼31 µJ/mm2. A high SMSR lasing signal was observed at a pump power of ~ 58.29 μJ/mm2.
