Observation of a nonlinear microfiber resonator

Area of Science:

• Optics and Photonics
• Materials Science
• Nonlinear Dynamics

Background:

• Silica microfiber resonators are key components in photonic integrated circuits.
• Understanding their nonlinear optical properties is crucial for device performance.
• Hysteresis in optical systems can arise from various physical mechanisms.

Purpose of the Study:

• To investigate the hysteresis observed in the intensity transfer function of silica microfiber resonators.
• To identify the underlying physical mechanism responsible for the observed hysteresis.
• To develop a predictive model for resonator behavior.

Main Methods:

• Experimental measurement of the intensity transfer function under varying cavity detuning and input power scanning frequencies.
• Development of a theoretical model based on thermal nonlinear phase shifts.
• Comparison of experimental data with model predictions.

Main Results:

• Observed a wide variety of hysteresis cycles in the intensity transfer function.
• Attributed the hysteresis to a nonlinear phase shift of thermal origin.
• A simple model successfully reproduced the experimental measurements.
• Determined a response time of approximately 0.6 ms.

Conclusions:

• Thermal nonlinearities are the dominant cause of hysteresis in silica microfiber resonators.
• The proposed simple model provides accurate predictions of resonator behavior.
• The fast response time of 0.6 ms is relevant for high-speed optical applications.