Terahertz holographic data storage with a 3D printed phase plate

Abstract A sub-terahertz holographic image of a two-dimensional 576-bit data code is produced using a diffractive phase-plate element. The phase plate was designed using a modified Gerchberg-Saxton iterative algorithm to encode a focused image of the data code into a phase modulation profile. The complex phase plate structure is fabricated from polylactic acid using fused deposition modeling, a common three-dimensional-printing technique. The design allows for a significantly simplified optical setup, consisting of a 0.14 THz diverging source, the holographic phase plate and a scanning detector, in co-linear alignment. The information stored in the data code is an example of a cryptography private key. Specifically, the private key for a Bitcoin wallet address. Convincing detection of the encoded information demonstrates a practical use case for terahertz holographic data storage, using a storage medium that can be fabricated with consumer-level three-dimensional-printing techniques.