摘要： Microresonator based Kerr frequency comb generation has many attractive features, including ultrabroad spectra, chip-level integration, and low power consumption. Achieving precise tuning control over the comb frequencies will be important for a number of practical applications, but has been little explored for microresonator combs. In this paper, we characterize the thermal tuning of a coherent Kerr frequency comb generated from an on-chip silicon nitride microring. When the microring temperature is changed by ~70 °C with an integrated microheater, the line spacing and center frequency of the comb are tuned respectively by -253 MHz (-3.57 MHz/°C) and by -175 GHz (-2.63 GHz/°C); the latter constitutes 75% of the comb line spacing. From these results we obtain a shift of 25 GHz (362.07 MHz/°C) in the comb carrier-envelope offset frequency. Numerical simulations are performed by taking into account the thermo-optic effects in the waveguide core and cladding. The temperature variation of the comb line spacing predicted from simulations is close to that observed in experiments. The time-dependent thermal response of the microheater based tuning scheme is characterized; time constants of 30.9 μs and 0.71 ms are observed. 其他題名： Opt Express 出版者： United States: Optica Publishing Group 出版日期： 2016-01-11 出處： Optics Express, 2016-01, Vol.24 (1), p.687- 資源來源： Optica Publishing Group Journals 識別號： ISSN: 1094-4087 識別號： EISSN: 1094-4087 識別號： DOI: 10.1364/oe.24.000687 識別號： PMID: 26832298
