Temporal cloak | Erase digital data from history
What if you could harness the fundamental nature of the universe to make your data completely secure? It might be possible sooner than you think. Researchers have managed to create a so-called temporal cloak that acts as a pocket in time through which data can pass and leave no trace. The temporal cloak is so complete, the event is entirely obliterated from history.
Recent years have been filled with announcements of rudimentary invisibility cloak technology that relies on bending light around an object. The temporal cloak idea is built on the same principles, but in this case light waves are pulled apart then compressed to generate time pockets that cloak events.
The first cloaking attempts in 2010 using laser pulses proved interesting experimentally, but the duration of the pockets was measured in a few picoseconds — not nearly enough to do anything useful. A team of researchers led by Joseph Lukens at Purdue University has been improving this process, carving out larger and larger pockets. The most recent breakthrough from this lab, as reported in Nature, makes use of a wave phenomenon called the Talbot effect. This time researchers have managed to completely obfuscate a huge amount of data.
The Talbot effect describes the way a diffraction grating produces an interference pattern of peaks and troughs when light is passed through it. The trick to creating the desired temporal effect is to convert the Talbot effect from something happening in space, to something happening in time.
With some frequency tweaking, the team was able to expand the time holes to a whopping 36 picoseconds. A picosecond is a trillionth of a second, so this might not sound like a terribly long time. For lasers, it’s a relative eternity, though. The researchers were able to successfully hide a data rate of 12.7 gigabits per second in an optical cable — almost half the total bandwidth.
This process ends up a little too perfect when it comes to data security. It’s as if the cloaked data never existed, and that makes it difficult for a valid recipient to get the message — forget about a malicious third-party. However, Lukens believes future modifications will allow secret messages to be sent with the temporal cloak. In the meantime, the same process could be used to improve the fidelity of data streams. The troughs produced by the temporal Talbot effect hide data, but the peaks could be used to reinforce it. Timing transmissions to the peaks could reduce crosstalk on busy lines and lessen the chance of corruption.
Most of the scientific advances around cloaking technology rely on exotic materials and special conditions, but not this time. Temporal cloaking can be accomplished in standard fiber optic cable. The authors speculate this technology could be used to hide and improve communications in the near future.
