All-optical memory based on surface plasmons and Kerr-type nonlinear cavity

• All-optical memory using MIM waveguides and Kerr cavity enables ultrafast switching and compact integration. • Achieves < 100 fs switching speed and ultra-low enable intensity of 7 MW/cm 2 via nonlinear plasmonic resonance. • Tunable operation across telecom wavelengths supports precise control through cavity and coupling design. • FDTD simulations confirm high transmission contrast, stability, and energy-efficient bistable switching. • Proposed design outperforms prior memory schemes in power efficiency, footprint, and integration density. This paper presents a novel ultra-fast all-optical plasmonic memory architecture designed for next-generation integrated photonic circuits. The proposed memory cell employs metal–insulator-metal (MIM) plasmonic waveguides integrated with Kerr-type nonlinear nanocavities to enable efficient all-optical switching. Through systematic finite-difference time-domain (FDTD) simulations, we demonstrate robust operation across standard telecommunication wavelengths while maintaining precise wavelength tunability. The optimized design achieves remarkable performance metrics, including an ultra-low enable intensity of 7 MW/cm 2 , a compact footprint of 1.2 μm 2 , and sub-100-femtosecond switching speeds. Detailed analysis of Poynting vector distributions reveals how plasmonic nanocavity resonances facilitate optical bistability, providing critical insights into the operational mechanism. Compared with existing all-optical memory solutions, our architecture offers superior power efficiency, enhanced transmission contrast, and higher integration density. These advantages position the proposed design as an ideal candidate for high-performance optical computing systems and on-chip memory applications, addressing key challenges in photonic data processing.