Quantum Computers Are Showing Promise, But the Real Revolution Is Quantum Internet, Which Is Already Underway

Quantum technologies extend beyond quantum computers. Although we often focus on quantum computers due to their remarkable progress in the past five years, there are other important advancements in this field. One example is the development of a quantum Internet, a large-scale quantum communications infrastructure that’s currently in progress. In July 2020, the Department of Energy (DOE) revealed its strategy for facilitating the advancement of the necessary technologies to establish a quantum Internet.

At the same time, the DOE announced a firm commitment to invest an initial $625 million in this project. China and the U.S. are the two major powers investing the most in quantum communications development, with Europe also making significant contributions. Establishing a quantum communications infrastructure with global coverage comparable to the current Internet network will allow for the instantaneous transfer of large volumes of information.

Additionally, data transmission will be inherently secure due to the entanglement between communication nodes, which is broken if the communication is breached or observed by unauthorized parties. However, it’s important to note that although these promises sound promising, quantum Internet isn’t intended to replace the current Internet.

Quantum Internet Is Getting Closer

When quantum Internet finally arrives, and we have good reason to expect that it will, it’ll coexist with the Internet we’re all familiar with, just as quantum computers are destined to coexist in perfect harmony with classical supercomputers. This begs the question: What sort of applications should we use with quantum Internet? The answer emerges by itself from the two properties of the network that we’ve just explored: its capacity to transfer large volumes of data instantaneously and the inherent invulnerability of quantum communications.

Stephanie Simmons is a physicist and former researcher at Harvard University. She’s also the co-founder of Photonic, a company specializing in quantum communications. Recently, she participated in an event organized by Economist Impact–a self-described think-tank, media brand, and global influence–and shared several statements that shed light on the potential of quantum Internet. Her company focuses on producing silicon spin qubits interconnected by photonic links to create a modular and scalable architecture.

“The key resource for distributed quantum computing is entanglement… Distributing entanglement is basically all of the use cases for networks… [The] better we get at entanglement distribution, the more quickly we can run those kinds of algorithms at scale,” Simmons said. She also emphasized that a system of interconnected qubits using photonic links allows for the entanglement of any two qubits, provided there’s a photonic connection between them.

This phenomenon has no equivalent in classical physics. It consists of the fact that the state of the quantum systems involved, which may be two or more, is the same. This means these objects are actually part of the same system, even though they’re physically separated. Distance doesn’t matter. If two particles, objects, or systems are intertwined by this quantum phenomenon, when we measure the physical properties of one of them, we’ll be instantly conditioning the physical properties of the other system with which it’s intertwined, even if it’s at the other end of the universe.

All the above suggests that quantum computers connected by photonic links will likely form a quantum Internet with unattainable capabilities for the network we’re all familiar with today. If this infrastructure eventually prospers and is properly implemented, scalability will no longer be an issue. It’ll be possible to interconnect so many qubits that in a way, the quantum Internet itself will behave like a gigantic quantum computer with millions of qubits. Let’s keep our fingers crossed these ideas come to fruition.

Image | IBM

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