NOV 17, 2016 06:30 AM PST

How 1930s radio technology could make the internet more secure

Image Credit: John Schneider/Flickr

If there’s ever going to be a totally secure quantum internet, we’re going to have to overcome some significant challenges.

Among the most critical will be devices that can send and receive quantum data. To that end, researchers at Stanford University have created a novel quantum light source that might someday serve as the basis for quantum communication. They explained their findings in a paper published in Nature Photonics.

The physics of quantum communication is admittedly complex. Standard lasers are actually not useful for secure communication because they emit what is called “classical” light. Data eavesdroppers could extract any data being carried via classical light without detection.

In contrast, a quantum internet would be based on “quantum” light, in which a single unit of light—a single photon—cannot be measured without being destroyed. Therefore, an efficient source of quantum light would enable perfectly secure communication.

Senior author Jelena Vuckovic, a professor of electrical engineering, has been working for years to develop various nanoscale lasers and quantum technologies that might help conventional computers communicate faster and more efficiently using light instead of electricity. She and her team, including lead author Kevin Fischer, a doctoral candidate, realized that a modified nanoscale laser can be used to efficiently generate quantum light for quantum communication.

“The problem is that the quantum light is much weaker than the rest of the light coming from such a modified laser—it is difficult to pick up,” Vuckovic says. “So, we created a way to filter out the unwanted light, allowing us to read the quantum signal much better.”

The filtering works in a fashion similar to the way noise-canceling headphones operate, only with light, instead of sound. With the headphones, a sensor actively gauges the frequency of relatively constant ambient sound—the rumble of traffic, the drone of an airplane engine, the thrum of a refrigerator—and produces a similar pattern, which can be used to cancel out the undesirable sound.

“Some of the light coming back from the modified laser is like noise, preventing us from seeing the quantum light,” Fischer says. “We canceled it out to reveal and emphasize the quantum signal hidden beneath.”

Vuckovic’s team adapted an interference technique borrowed from 1930s-era radio engineering to cancel the unwanted classical light. They first figured out what the “noise” looks like and played it back. By carefully adjusting how the canceling light and the classical light overlap, the unwanted light is canceled and the once-hidden quantum light is revealed.

“This is a very promising development,” Vuckovic says. “It provides us with a practical pathway to secure quantum communications.”

She and her team are now working on creating a working prototype.

Source: Stanford University

This article was originally published on Futurity.org.
About the Author
  • Futurity features the latest discoveries by scientists at top research universities in the US, UK, Canada, Europe, Asia, and Australia. The nonprofit site, which launched in 2009, is supported solely by its university partners (listed below) in an effort to share research news directly with the public.
You May Also Like
OCT 19, 2019
Neuroscience
OCT 19, 2019
Smartphone-controlled brains?
A team of scientists in Korea and the United States have developed a tiny, flexible, wireless device that can control neurons and neural circuits in the mo...
OCT 19, 2019
Space & Astronomy
OCT 19, 2019
Say Hello to Hubble's Latest Portrait of Jupiter
NASA takes advantage of the Hubble Space Telescope’s powerful imaging capabilities to photograph both neighboring and distant objects in space, and s...
OCT 19, 2019
Chemistry & Physics
OCT 19, 2019
Quantum Darwinism: the Quirky Marriage of Two Distant Theories
Charles Darwin wouldn't have foreseen that one day his theory of natural selection would be borrowed to explain a puzzle that has bothered quantum phys...
OCT 19, 2019
Space & Astronomy
OCT 19, 2019
What We've Learned About Mars From India's Mangalyaan Mission
Back in 2013, the Indian Space Research Organization (ISRO) launched a Mars-orbiting spacecraft dubbed the Mars Orbiter Mission (MOM), also known as Mangal...
OCT 19, 2019
Technology
OCT 19, 2019
Technology Helps Parents Understand Their Baby
Researchers at the University of York may now help parents understand what their babies are thinking through an app called ‘BabyMind’. The app ...
OCT 19, 2019
Microbiology
OCT 19, 2019
Scientists Capture Video of a Virus Forming
In a first, scientists have captured video of individual viruses as they form, illustrating viral assembly....
Loading Comments...