Nonlinear model analysis of all-optical flip-flop and inverter operations of microring laser

Abstract

We explore a theoretical model of bistability at two adjacent lasing wavelengths from an InGaAs/InGaAsP multiple quantum well (MQW) microring laser. We show that nonlinear effects on the phase and amplitude play significant roles in the lasing operations of the microring laser. Numerical simulations indicate that all-optical flip-flop operations and inverter operations can be observed within the same device by controlling the injection current. The validity of our analysis is confirmed by a comparison of the results for numerical simulations with experimental results of the lasing spectrum. We believe that the analysis presented in this paper will be useful for the future design of all-optical signal processing devices.

Switchable All-Optical Flip-Flop and Inverter Operations in Quantum Well Microring Laser

“…The principle of the all-optical flip-flop and inverter is based on the injection locking in the laser and the XGM between the main lasing wavelength and the adjacent one, as mentioned in Section II. We found that both operation modes are realized in the same microring laser [33] and proposed analysis model for the switching of operations without discriminating between CW and CCW lasing directions [34]. However, there are some discrepancies between the theoretical and experimental results.…”

“…The basic principle of the proposed all-optical flip-flop and inverter devices is discussed in [33,34]. The flip-flop is operated by the injection locking at the resonant wavelength next to the main lasing wavelength in the microring laser.…”

“…The remaining light power propagating in the CCW direction is increased by R F (), that is, the power coupling efficiency K () is effectively decreased by R F (). Therefore, the effective power coupling efficiency KF () is obtained as [34] …”

“… pF () and  pB () are the photon lifetimes in the MRR for the forward (CCW) and backward (CW) lasing directions at , respectively, given by [34]  …”

“…Therefore, the proposed microring laser-based flip-flop and inverter are promising candidates for waveguide-type integrated all-optical logic devices. Thus far, we have analyzed the mechanism of the flip-flop and inverter operations in the same device [34]. In a theoretical analysis, a model of the nonlinear effects on the phase and light amplitude in a busline waveguide was introduced, and the fundamental operating mechanism was clarified, although lasing directions in a microring laser were not considered in the rate equations.…”