Perfect tunable all-optical diode based on periodic photonic crystal grand graded structures

We have investigated nonlinear properties and optically diode action capability in graded nonlinear one-dimensional photonic crystals-made up of graded index and thickness layers using transfer matrix method (TMM). We have considered the efficacy of index and thickness gradient parameters on the nonlinear properties in right to left and left to right optical pumping. It is found that the difference between the up-switch threshold input intensities of the left to right and right to left impinging lights and optical bistability (OBS) threshold can be tunable with thickness gradation parameter and index gradation parameter respectively. Proposed structure can be useful in designing low threshold and high speed optical diode switches and rectifiers. © 2019 Walter de Gruyter GmbH Berlin/Boston 2019.