Ultra-fast all-optical memory based on hexagonal photonic crystal lattice on a GaAs substrate

• The operation speed of the presented optical memory is considerable. • The small size of the proposed structure is its major advantage to realize compact optical integrated circuits. • The proposed structure works in the telecommunication wavelength and it is suitable to all-optical communication processors. In this paper, a novel photonic crystal (PhC) all-optical memory is proposed. It is based on a hexagonal lattice of air holes on a GaAs substrate. The structure is numerically simulated using the finite difference time domain (FDTD) method. This structure utilizes the nonlinear Kerr effect properties of a photonic crystal cavity to achieve high-speed performance with a rise time of <0.21 ps. The high Q factor of the hexagonal cavity, combined with the use of Kerr material, results in reduced power consumption for both the data and bias signals, reaching below 3 μW/μm. Additionally, the reduction in the dimensions of the structure to approximately 30 μm 2 is significant and noteworthy compared to recent works. Our innovative design highlights significant advancements in speed and power efficiency for the designed all-optical memory, suggesting promising applications in photonic integrated circuits.