Storage capacity of holo-interferograms

Area of Science:

• Optical Engineering
• Materials Science
• Data Storage

Background:

• Holographic data storage offers high potential capacity.
• Understanding practical limitations is crucial for realizing this potential.

Purpose of the Study:

• To experimentally determine the practical storage capacity of a holographic medium.
• To identify and quantify noise sources limiting storage density.

Main Methods:

• Recording simultaneous, orthogonally polarized volume holograms of an information-dense object.
• Interferometric registration and CCD scanning of reconstructed holograms.
• Analysis of noise contributions from grain and emulsional plasticity.

Main Results:

• Achieved imprint densities up to 4.1 x 10(10) bits/cm3.
• Identified grain noise in moderately dense data and plasticity noise in sparse/extremely dense data.
• Practical retrieval limited to 2.7 x 10(10) bits/cm3 due to plasticity noise.

Conclusions:

• Emulsional plasticity is a critical factor limiting practical holographic storage capacity.
• The determined capacity is two orders of magnitude below theoretical estimates based on bandwidth and grain noise alone.
• Further research into mitigating plasticity noise is needed for advanced holographic data storage.