We present a novel and simple method to obtain an ultrawide free spectral range (FSR) silicon ring resonator together with a tuning range covering the entire spectrum from 1500 to 1600 nm. A ring resonator with a large FSR together with a high Q factor, high tuning efficiency, and low fabrication cost and complexity is desired formany applications. In this paper, we introduce a novel way to make such a ring resonator, which takes advantage of the well-known resonance-splitting phenomenon. It is
