Three-dimensional optical data storage in refractive media by two-photon point excitation

Area of Science:

• Optics and Photonics
• Materials Science
• Data Storage Technologies

Background:

• Current optical data storage methods face limitations in capacity and density.
• Advancements in laser technology and photopolymer materials offer new possibilities for data recording.

Purpose of the Study:

• To report the first high-density optical recording of digital information in a multilayered, three-dimensional format.
• To demonstrate a novel method for increasing data storage capacity using submicrometer volume elements.

Main Methods:

• Utilizing two-photon excitation of a photoinitiator within a photopolymer to create submicrometer volume elements.
• Employing a colliding-pulse mode-locked laser to focus light and confine polymerization to the focal volume.
• Reading information using differential interference contrast microscopy with high axial resolution.

Main Results:

• Achieved high-density optical recording exceeding 10(12) bits/cm(3).
• Demonstrated successful writing and reading of digital information in a 3D, multilayered format.
• Confirmed that the two-photon excitation's quadratic dependence effectively confines polymerization.

Conclusions:

• This write-once, read-many technique represents a significant advancement in optical data storage.
• The reported method has the potential to increase the capacity of spinning disk formats by 100-fold.
• This 3D optical recording approach offers a scalable solution for future high-capacity data storage needs.