Unscramble This

The uncertainty principle, a fundamental concept of quantum mechanics, states that the more precisely one determines the position of a subatomic particle, the less precisely one can determine its momentum. Werner Heisenberg figured out that one in the 1920s, and physicists since have grappled with the conundrum: that the very act of observing a particle impacts the particle being observed. In this challenge, Steve Olmschenk sees an opportunity.

An assistant professor in the Department of Physics and Astronomy, Olmschenk heads up the college’s Ion Quantum Optics Group, which is researching new applications for quantum information. One aspect of that research—one the U.S. Army Research Office last year deemed worthy of a Young Investigator grant—focuses on the potential for storing information at the atomic level. Within that massive leap from classic information—the flow of binary data of ones and zeroes that defines our current digital world—lies a solution that could transform the way data are protected.

“Quantum mechanics has told us that if we get to a really small scale, dealing with things the size of atoms, things are allowed to be in two states at once. If we can store information in an atom, we could store it as a zero or one, or as some combination: zero plus one, or zero minus one,” Olmschenk explains.

Confused? That’s (sort of) the point. The idea is that by integrating, say, a single trapped atomic ion with a single photon of light, as Olmschenk’s lab is attempting, it would be possible to store and transmit sensitive information on the photon; if some snooping foe tried to intercept that information, the photon would bear irrefutable physical proof of the attempt. As Heisenberg understood, the act of observing will leave a telltale trace on the particle being observed. “You’ll know if someone looked at it along the way,” Olmschenk says. “It’s really a new way to think about encryption.”

That’s only one narrow application of expanding research in the field of quantum information, which Olmschenk says boasts vast potential for new knowledge. “The general idea with quantum information is, it’s all there; the hard part is implementing it in the lab,” he says. “It’s allowing us to probe things that were predicted by quantum mechanisms to exist, but that we didn’t have any way to measure. That’s a beautiful thing.”

Published March 2014