Critical Dynamics of a Nonlinear Enhanced Microresonator Gyroscope

Summary form only given. Recent work [1-4] has demonstrated spontaneous breaking of clockwise-counterclockwise symmetry in a bidirectionally-pumped passive optical microresonator, mediated by the Kerr effect. The critical point of this symmetry breaking exhibits universal behaviours such as sensitivity enhancement and critical slowing down, which make it useful for sensing applications such as microresonator-based optical gyroscopes [5,6]. Here we explore the dynamics close to this critical point in the context of a nonlinear enhanced Sagriac gyroscope (see Fig. 1). The detuning difference between the pump laser light in the two directions is modulated sinusoidally at various frequencies in the 1 kHz range, which is much slower than the resonator's linewidth of 1 MHz, to simulate a sinusoidal rotation. This produces a response in the form of a modulated difference between the in -coupled optical powers in the two directions, which is more amplified the closer the system is to the critical point. In our experiment, this amplification factor typically reaches -10 4 . The amplitude and phase of the system's response at the modulation frequency agree well with simulations based on a simplified theoretical model. In the critical regime, the system has enhanced sensitivity both to pump detuning and power differences. In the simulation, 1/f noise was added to the pump frequencies to mimic the residual power noise in the experiment.