Recent advances in holographic data storage

Abstract

Nowadays, big-data centers still rely on hard drives. However, there is strong evidence that these surface-storage technologies are approaching fundamental limits that may be difficult to overcome, as ever-smaller bits become less thermally stable and harder to access. An intriguing approach for next generation data-storage is to use light to store information throughout the threedimensional (3D) volume of a material. Holographic data storage (HDS) is poised to change the way we write and retrieve data forever. After many years of developing appropriate recording media and optical read-write architectures, this promising technology is now moving industriously to the market. In this paper, a review of the major achievements of HDS in the past ten years is presented and the key technique details are discussed. The author concludes that HDS technology is an attractive candidate for big data centers in the future. On the other hand, there are many challenges ahead for HDS technology to overcome in the years to come.

Ultra-high density optical data storage in common transparent plastics

“…Even higher capacities of up to 1 Tbits/cm 3 were explored in 5D technology by utilizing the unique properties of surface plasmon resonance of gold nanorods stacked in multiple layers and using non-Gaussian laser beams to imprint the data 5 6 12 . Holography is an alternative technology capable of high-density data storage but it also requires photosensitive recording medium 13 14 15 .…”

Multiplexed holograms recorded in a low toxicity Biophotopol photopolymer

“…From the Fig 1 it can be seen that the slanted gratings recorded have a shift from their original register angle. This displacement is a consequence of the shrinkage that appears due to a film thickness variation 2,7 . In some gratings, it is also possible to see the secondary lobes that appear in the slanted gratings ( i.e.…”

“…Recently, the Biophotopol photopolymer capability as a data recording material has been demonstrated using two different peristrophic multiplexing techniques 1 . These techniques are commonly used in holographic data storage experiments [2][3][4] . Peristrophic multiplexing is a very useful tool especially when the holographic recording medium is relatively thin.…”

Convolutional neural network-based data page classification for holographic memory

“…In holographic memory [1,2], digital data is converted into a two-dimensional pattern called a data page, and this is recorded on a recording medium as a hologram. The main features of the holographic memory are below: (1) the access speed is fast because the data page can be read and written as twodimensional images, and (2) multiple data pages can be stored in the same recording area by multiplex recording characteristics of holography, leading to an increase in the memory capacity.…”