Development and numerical simulation of tellurite glass microresonators for optical frequency comb generation

Abstract We present the first theoretical analysis of optical frequency comb generation in tellurite microresonators with whispering gallery modes. The regime of dissipative soliton generation is simulated numerically in tellurite microbubbles pumped at 1.95 μm or at 2.3 μm by a Tm-doped tellurite fiber laser. Using microbubble geometry allows controlling the zero dispersion wavelength and obtaining anomalous dispersion needed for soliton generation at both pump wavelengths, whereas the zero dispersion wavelength of the analyzed TeO2-WO3-La2O3 glass is 2.17 μm. The glass parameters measured in the previous experiments are used for modeling. It is shown that for the optimized characteristics of microbubbles, optical frequency combs with a spectral width of 200 nm (at the level of −30 dB) can be obtained with a low pump power threshold of about a few mW. Ultrashort pulses with a duration of about 130 fs and repetition rates of a few hundred GHz correspond to these combs in the time domain.