Taking a cue from an early 20th century technology, researchers at Stanford University have created a novel technology that can help improve internet security. The study shows how harnessing the quantum properties of light can create a transmission technology impervious to eavesdropping.
Jelena Vuckovic, professor of electrical engineering at Stanford, has been working for years to develop various nanoscale technologies that can help conventional computers communicate faster and more efficiently using light instead of electricity.
She and her team demonstrated 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 explained.
"So, we created a way to filter out the unwanted light, allowing us to read the quantum signal much better," she added in a paper published in the journal Nature Photonics. The filtering works in a fashion similar to the way noise-canceling headphones operate - only with light instead of sound.
The team adapted an interference technique borrowed from 1930s-era radio engineering to cancel the unwanted classical light. "This is a very promising development and provides us with a practical pathway to secure quantum communications," Vuckovic said. She and her team are now working on creating a working prototype.