A Texas A&M University quantum physicist has uncovered an "almost psychic communication."
M. Suhail Zubairy, an A&M physics and astronomy professor, along with a post-doctoral fellow and Saudi researchers developed a way for two parties to communicate without using physical particles, or photons, suggesting information can travel between two parties in an unusual way.
Zubairy said the research would have major applications for communications security, such as existing measures that secure transfer of credit card information between consumer and vendor. With the new data, there would be no data to steal within the communication channel in the first place.
"Right now, this is a new, beautiful idea," said Zubairy, who is a member of A&M's Institute for Quantum Science and Engineering. "I'm looking at it like a painter or poet looks at art or poetry. Could there be use? Yes, but our main goal right now was simply to understand the basic science first. Who knows what kinds of applications could be envisioned in the future."
In the paper, the researchers describe an interaction between "Alice" and "Bob" using a series of beam splitters. Information was exchanged between the two without any photons - tiny units of electromagnetic light - passing through the communication channel. That is a new paradigm in quantum communication, Zubairy said.
In the setup, a photon leaving Alice's station can either be absorbed or not by Bob. Depending on what he chooses, different detectors are set off on Alice's end, so she can figure out his choice just by checking her own detectors.
"In technical terms, we call this 'counterfactual,'" Zubairy said. "It's been believed that if two parties want to communicate, something needs to be sent, and something is allowing for its passage. That's been an underlying assumption in every communications system. This is the first possible setup where that doesn't exist. That's what I mean by 'almost psychic.'"
The research will be published in the April 26 edition of Physical Review Letters and was reviewed earlier this week in Physics World. Zubairy co-authored the paper along with a Texas A&M post-doctoral fellow, Zheng-Hong Li, and two researchers from the National Center for Mathematics and Physics at the King Abdulaziz City for Science and Technology in Saudi Arabia, Hatim Salih and Mohammad Al-Amri.
"What we are proposing goes a couple steps beyond that," Zubairy said. "We are talking about direct communication, not through a key. Now we have a protocol for eliminating the middle man. From a fundamental point of view, this is amazing. It sort of brings up these old questions, such as what is a photon?"