Yichi Zhang, a doctoral student in Materials Science and Engineering, inspects the source of the quantum signal. Credit: Sylvia Zhang (CC BY-SA)<\/p>\n
Quantum networking may be one step closer to commercial use with engineers from the University of Pennsylvania in the US designing a \u2018Q-chip\u2019 that can transport quantum data onto modern internet networks.<\/p>\n
The experiment, published in Science<\/a>, brought quantum networking out of the lab, where it has traditionally been studied, and into the fibre-optic cables used in commercial settings for everyday online connections.<\/p>\n The researchers hope that this design will set the stage for the potentially transformative \u201cquantum internet\u201d future.<\/p>\n \u201cThis feels like the early days of the classical internet in the 1990s, when universities first connected their networks,\u201d says Robert Broberg, an electrical and systems engineering doctoral student at Penn and coauthor of the paper.<\/p>\n \u201cThat opened the door to transformations no one could have predicted. A quantum internet has the same potential.\u201d<\/p>\n Quantum networks rely on pairs of \u2018entangled\u2019 particles<\/a>, where a change to one instantaneously causes the same change to happen in the other. Researchers hope that if they can harness this entangled property, it could enable them to combine all the processing power together and link up quantum computers.<\/p>\n This type of network could enable faster, more energy-efficient AI <\/a>exceeding what can currently be achieved with super computers. The implications could also stretch into the world of medicine, with a study<\/a> published in January using quantum computing to help design an anti-cancer drug.<\/p>\n However, the unique nature of \u2018quantum entanglement<\/a>\u2019 makes developing such a network very difficult. As discovered by Erwin Schrodinger, quantum particles lose their quantum properties when observed, which makes calibrating a quantum network an almost impossible task for scientists.\u00a0<\/p>\n \u201cNormal networks measure data to guide it towards the ultimate destination,\u201d says Broberg.<\/p>\n \u201cWith purely quantum networks, you can\u2019t do that, because measuring the particles destroys the quantum state.\u201d<\/p>\n Despite this obstacle, the team at Penn has shown that their \u2018Q-chip\u2019 can send quantum signals over live commercial fibre. They were able to do so by coordinating quantum signals and classical signals that come from regular light particles.<\/p>\n \u201cThe classical signal travels just ahead of the quantum signal,\u201d says Yichi Zhang, the study\u2019s first author from Penn\u2019s Materials Science and Engineering (MSE) faculty.<\/p>\n \u201cThat allows us to measure the classical signal for routing, while leaving the quantum signal intact.\u201d<\/p>\n