Control of gold nano-domes to design an all-optical switch by simultaneously binary and continuous operated optimization

This paper presents an efficient evolutionary method to optimize an array of plasmonic nano-domes in order to design an optical switch. In the proposed switch, the optical switch has been excited by two monochromatic incident plan-waves with the same frequency and two polar angles “\(\uptheta =0\)” and “\(\uptheta =\uppi /2\)”. When only the signal with \(\uptheta =0\) is applied, the incident wave is transmitted and when both signals are applied to the switch simultaneously, coherent perfect absorption (CPA) occurs and the two incident waves are suppressed. Therefore, the signal with \(\uptheta =\uppi /2\) acts as control signal. Since the CPA efficiency depends strongly on the number of plasmonic nano-domes, on their location and geometric characterization, a new efficient optimization method named “fuzzy adaptive modified particle swarm optimization” (FAMPSO) is proposed to design an optimized array of the plasmonic nano-domes in order to achieve the maximum absorption coefficient in the off-state and the minimum absorption coefficient in the on-state. In the FAMPSO algorithm a group of birds controlling the presence (‘1’) or the absence (‘0’) and geometric characterization of nano domes in the array.