Optical characterization of on-chip silicon nitride microresonators

Abdullah Al Noman, Purdue University


Optical Characterization of on-chip microresonators is very important in microresonator research area. Full optical characterization includes both the time and the frequency domain characterizations by which we can get some basic parameters and properties like Free Spectral range (FSR), Quality Factor, Dispersion, ability to generate coherent Frequency Comb etc. These parameters and properties are very important because a lot of applications of microring resonators depend on the value of those parameters that we obtain from optical characterizations. In this thesis, we tried to describe some of the fundamental frequency domain characterization methods namely the Transmission Spectrum measurement, Quality factor measurement, Dispersion measurement and Optical Frequency Comb generation. The major contribution of this thesis is the development of an improved dispersion measurement scheme which reduced the complexity of the previous design and simplified the measurement process. The modified dispersion measurement scheme, which uses the FSR evolution and spectroscopy method, can measure dispersion very precisely and in a more efficient way.