Performance analysis of all-optical 1-bit comparator using 2D-PhC nonlinear ring resonators based on threshold switching method

In this research, an all-optical 1-bit comparator (AOCMP) is designed using two-dimensional photonic crystals (2D-PhCs) nonlinear ring resonators (NRRs), and its performance is analyzed based on the threshold switching method. By optimizing the structural parameters of NRRs, such as the refractive index and radius of the rods, this resonator can operate with desired wavelength (1550 nm) within the operating frequency range determined by the transverse magnetic (TM) band diagram. The performance of the proposed AOCMP is analyzed in terms of various factors such as optical switching power, bit rate, time delay, and ON-OFF contrast ratio that are calculated using a finite difference time domain (FDTD) simulation. Also, the operating frequency range (the wavelength range of 1355-2178 (nm)) is investigated using the plane wave expansion (PWE) method. The optimized optical device has exhibited a high contrast ratio of 10.36 dB within a very small size of 325 ${\rm{ \mu }}{{\rm{m}}<^>2}$mu m2.