2025/06/18 by Wenhan Sun, Sun, Wenhan, Ruixuan Wang +9
Engineering · #Applied Physics (physics.app-ph) #FOS: Physical sciences #Optics (physics.optics) #Thin-Film Transistor Technologies
paper · pdf · doi:10.48550/arxiv.2506.15035
openalex publication_date 2025/06/18 · openalex created_date 2025/10/19 · openalex updated_date 2026/07/28
Recent progress in the 4H-silicon-carbide-on-insulator (4H-SiCOI) platform has resulted in the demonstration of essential building blocks such as low-loss waveguides and microresonators. In this work, we add tunability to the 4H-SiCOI platform by integrating microheaters with compact microresonators. The strong thermo-optic effect in SiC enables a resonance tuning rate of 11.7 pm/mW for a 36-μm-radius SiC microring, with a maximum wavelength shift up to 2.4 nm (300 GHz). The thermal time constant of the microheater is estimated near 7 μs, corresponding to a 3-dB electrical bandwidth of 40 kHz. As a demonstration of potential applications, we employ the microheater to perform fast thermo-optic scans to deterministically access the single-soliton state of a 36-μm-radius microcomb source. In addition, an add-drop filter based on an over-coupled 18-μm-radius SiC microring is combined with the microcomb source for the selective filtering of individual comb lines, featuring an approximate 3-dB bandwidth of 5 GHz and an insertion loss of less than 1 dB. With such demonstrations, our work brings the much-needed tunability and reconfigurability to the 4H-SiCOI platform, paving the way for a wealth of chip-scale applications.