Broadband mid-infrared frequency comb generation in a Si3N4 microresonator

摘要

We demonstrate broadband frequency comb generation in the mid-infrared (MIR) from 2.3 to 3.5 mu m in a Si3N4 microresonator. We engineer the dispersion of the structure in the MIR using a Sellmeier equation we derive from experimental measurements performed on Si3N4 films from the UV to the IR. We use deposition-anneal cycling to decrease absorption losses due to vibrational transitions in the MIR and achieve a Q-factor of 1.0 x 10(6). To our knowledge, this is the highest Q reported in this wavelength range for any on-chip resonator. (C) 2015 Optical Society of America