A Time Cloak Made from Lasers Can Erase Data from History

Illustration for article titled A Time Cloak Made from Lasers Can Erase Data from History

Time cloaks are so much cooler than invisibility cloaks because they use freaking time to hide things, not silly dumb vision tricks. This new method of using a time cloak is the first that can cloak data at rapid rates. It might change security altogether.


The idea behind a time cloak is sort of simple (well, not really), if you pull light waves apart in time and then compress them back together, it should be possible to create time pockets to cloak things (just trust the theory, it's easier for us small brains to live with). Researchers at Cornell built the first working time cloak by using laser pulses. It was awesome.

Not so awesome was how long it took. There just wasn't enough time windows to hide data coming it at rapid rates. So to make a faster, more usable time cloak, Joseph Lukens, an electrical engineer at Purdue University in Indiana, and his colleagues used a phase modulator.

A what? Scientific American explains:

Lukens' team created its Talbot carpet in time by passing laser light through a 'phase modulator', a waveguide that also had an oscillating electrical voltage applied to it. As the voltage varied, the speed at which the light traveled through the waveguide was altered, splitting the light into its constituent frequencies and knocking these out of step. As predicted, at regular time intervals, the separate frequencies recombined destructively to generate time holes.

Neat. The cloak that Lukens created could hide data at 12.7 gigabits per second. That's pretty fast. Light. Time. Cloaks. Read more about the fascinating report here. [Scientific American]



"if you pull light waves apart in time" Oh well when you put it that way, sounds downright simple.