Monolithic tantalum pentoxide microrings with intrinsic Q factors exceeding 4✖10^6

The dataset presented herein corresponds to the research work reported in the paper entitled "Monolithic tantalum pentoxide microrings with intrinsic Q factors exceeding 4×10⁶". This dataset includes scanning electron microscopy (SEM) characterization images, atomic force microscopy (AFM) surface roughness data, transmission spectrum datasets in the telecommunications band, and quality factor (Q factor) measurement data of the Ta₂O₅ microring resonators. All the aforementioned data are raw experimental data directly recorded during the experiments, which were conducted in Shanghai from October 2025 to January 2026.The surface roughness data were obtained via AFM characterization. The transmission spectra were measured using a tunable external-cavity diode laser with a linewidth < 200 kHz, covering the 1520-1570 nm telecommunications band, with a rough scanning precision of 0.01 nm. The Q factor-related dataset consists of one set of independent measurement data, and the resonant mode parameters are extracted through Lorentzian line-shape fitting to ensure measurement accuracy.