New holographic data storage approach packs more data into the same space
Researchers combine amplitude, phase and polarization for faster, higher-capacity 3D data storage
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Researchers developed a holographic data storage approach that stores and retrieves information in three dimensions by combining the amplitude, phase and polarization properties of light.
view moreCredit: Xiaodi Tan, Fujian Normal University in China
WASHINGTON — Researchers have developed a holographic data storage approach that stores and retrieves information in three dimensions by combining three properties of light — amplitude, phase and polarization. By allowing more data to be stored in the same space, the new approach could help advance efforts to meet the growing global demand for data storage.
Holographic data storage uses laser light to store digital information inside a material. Instead of recording data only on a surface, like a hard drive or optical disc, it stores many overlapping light patterns throughout the volume of the material, allowing much higher storage density and faster data transmission.
“In conventional holographic data storage, data encoding typically uses one light dimension such as amplitude or phase alone, or, at most, combines two of these dimensions,” said research team leader Xiaodi Tan from Fujian Normal University in China. “Based on the principle of polarization holography, we used a deep learning architecture known as a convolutional neural network model to enable the use of polarization as an independent information dimension.”
In Optica, Optica Publishing Group’s journal for high-impact research, the researchers describe their new holographic data storage technique and demonstrate that it can increase information density while also simplifying readout.
“With further development and commercialization, this type of multidimensional holographic data storage could enable smaller data centers and more efficient large-scale archival storage, while also enhancing data processing and transmission efficiency,” said Tan. “It could also contribute to safer data transmission, optical encryption and advanced imaging.”
Using polarization to store information
Holographic data storage records information as image-like data pages formed by laser light patterns. Encoding converts digital data into these pages for recording, and decoding restores the recorded pages back into user data.
Although multiple properties of light can theoretically be used to encode more information in each data page, doing so in practice is challenging. To address this, the researchers have spent years refining tensor-based polarization holography, which preserves the polarization state recorded in the hologram during reconstruction. This allows polarization to serve as a reliable channel for storing information.
In the new work, they developed a 3D modulation encoding scheme by controlling the intensity and phase of two orthogonal polarization states and using a double-phase hologram approach. This enabled a single phase-only spatial light modulator to encode amplitude, phase and polarization information in the optical field.
Decoding combined amplitude, phase and polarization (3D) information is difficult because sensors only detect light intensity (amplitude) and cannot directly sense phase and polarization. The researchers solved this problem by utilizing tensor-polarization holography theory and designing a convolutional neural network model to simultaneously retrieve 3D information directly from diffraction intensity images.
The model learns the amplitude, phase and polarization features of the optical field from two complementary diffraction images: one captured with a vertical polarizer and one without. By using these intensity images as inputs, the trained neural network can simultaneously decode amplitude, phase and polarization, which achieves increasing storage density and enhancing transmission speed.
Decoding with a neural network
After validating the theory behind the new method, the researchers built a compact setup to record and reconstruct the encoded optical field in a polarization-sensitive medium. During evaluation and decoding, the recorded intensity images were analyzed to identify amplitude, phase and polarization signatures in the intensity distributions. These signatures were then used as inputs for neural network decoding so that 3D data could be reconstructed simultaneously from intensity-only measurements.
“Overall, our results showed that multidimensional joint encoding substantially increased the information carried by a single holographic data page, thereby improving storage capacity,” said Tan. “In addition, neural network synchronous decoding reduced the need for complex measurements and step-by-step reconstruction, supporting more efficient readout and decoding. This could enable a practical route toward high-capacity, high-throughput holographic data storage.”
The researchers note that this work remains a research-stage demonstration, with further work needed before commercialization. To make it more practical for real-world operating conditions, they plan to increase the gray levels of coding to further expand capacity and improve the recording media’s long-term stability, uniformity and repeatability. They also want to combine the system with volumetric holographic multiplexing approaches to enable multi-page, multi-channel storage and strengthen the co-integration of optical hardware and decoding algorithms for faster, more robust data retrieval under practical conditions.
Paper: R. Chen, J. Wang, H. Wu, M. Song, Y. Yang, D. Lin, X. Tan, “Encoding and decoding of multidimensional optical field modulation in holographic data storage” 13, (2026).
DOI: 10.1364/OPTICA.586593.
About Optica
Optica is an open-access journal dedicated to the rapid dissemination of high-impact peer-reviewed research across the entire spectrum of optics and photonics. Published monthly by Optica Publishing Group, the Journal provides a forum for pioneering research to be swiftly accessed by the international community, whether that research is theoretical or experimental, fundamental or applied. Optica maintains a distinguished editorial board of more than 60 associate editors from around the world and is overseen by Editor-in-Chief Thomas Krauss, University of York, UK. For more information, visit Optica.
About Optica Publishing Group
Optica Publishing Group is a division of the society, Optica, Advancing Optics and Photonics Worldwide. It publishes the largest collection of peer-reviewed and most-cited content in optics and photonics, including 18 prestigious journals, the society’s flagship member magazine, and papers and videos from more than 835 conferences. With over 400,000 journal articles, conference papers and videos to search, discover and access, our publications portfolio represents the full range of research in the field from around the globe.
Journal
Optica
Article Title
Encoding and decoding of multidimensional optical field modulation in holographic data storage
The image shows (a) the holographic data storage system schematic diagram, (b) a schematic diagram illustrating the complex plane for double-phase decomposition of complex amplitude and (c) an example of a checkerboard pattern for two phase values m and n. Also shown are (d) an example of the intensity distribution at the image plane and (e) an example of phase distribution at the image plane. In (f), the first (I) and second (II) records are shown, with the readout shown in (g).
Credit
Xiaodi Tan, Fujian Normal University in China
The research team involved in developing the new holographic data storage approach.
Credit
Xiaodi Tan, Fujian Normal University in China
Retrieving 3D information from diffraction intensity images [VIDEO]
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