Measurement of Frequency Tuning Curves of Soliton Self-Injection Locking to a Nonlinear Microresonator

Self-injection locking effect eliminates the need for bulky narrow-linewidth, tunable, continuous-wave laser for pumping of high-Q optical microresonators, utilizing bare laser diodes. Here we propose an experimental technique, which allows measuring the main characteristic of self-injection locking, a frequency tuning curve. We measure tuning curves of locking to linear and nonlinear microresonators and compare them to the theoretical model.