PSTOST

PSTOST, short for Photonic Storage, Transfer, and Optical Signal Transmission Technology, refers to a proposed framework for next‑generation data architectures that aim to combine nonvolatile optical storage with on‑chip photonic interconnects and in‑memory processing. The concept envisions storing data directly in optical form, moving it through on‑substrate transfer channels, and transmitting signals across a silicon photonics backbone to processing elements, with the goal of reducing energy use and latency for select workloads.

The core idea of PSTOST is to integrate three functions on a single platform: a photonic storage layer, optical transfer pathways, and signal transmission to computational units. Storage may employ holographic, phase‑change, or other optical media. Transfer channels use waveguides and optical switches to route data without converting it to electronic form, while computation can be performed by photonic accelerators or tightly coupled electronic‑photonic processors. The architecture emphasizes co‑design of materials, optics, and circuitry to enable in‑place data access and sparse electronic activity.

Technical considerations include material stability, write/read endurance, thermal management, and the challenge of seamless CMOS integration. Prototypes often focus on small scales to demonstrate data retention, switching speeds, and compatibility with existing fabrication processes. Packaging and cooling remain key obstacles to broad deployment. Economic viability depends on achieving clear advantages in bandwidth density and energy efficiency for targeted workloads such as AI inference, archival storage, and high‑performance computing.

PSTOST remains an area of active research rather than a commercial standard. Ongoing work seeks to define viable material stacks, integration schemes, and software models to exploit its potential advantages. See also optical storage, photonic integrated circuits, and in‑memory computing.