Design of a Two-Photon Single-Laser Optical Data Storage System in a Multilayer Structure

In this paper, we investigate the two-photon recording system in a 50-layer structure with each recording layer contains 4.7GB of data, similar to the capacity of a single layer Digital Versatile Disc, as the total capacity is 235GB/disc. We present a single-laser system to realize recording and reading and propose a new multilayer disc structure in which the groove structure is set on the substrate for servo control, the laser is separated by a PBS to two parts, one for recording and the other for servo in the optical system. Our research shows the feasibility of high density optical data storage using a single laser in a multilayer structure.