The world continues to make progress in the realm of quantum computing. Each discovery and advancement brings us closer to a reality in which quantum computers and networks are the norm. Researchers are using ultracold molecules to store information, developing a new type of quantum computing, and researchers in China are working on an "unhackable" quantum communications network.
Now, a team of Canadian and U.S. researchers has taken an all-important step towards making quantum networks more realistic, affordable, and secure. Their work, published in the journal Quantum Science and Technology, explains the benefits of using measurement-device-independent quantum key distribution (MDI-QKD) systems.
The team used commercially available and relatively cheaper components like distributed feedback (DFB) lasers and field-programmable gate arrays (FPGA) to make their experimental system. According to senior author Dr. Qiang Zhou, this MDI-QKD system allows quantum bits (qubits) to generate keys in random states, making them harder to individually identify.
Securing Quantum Networks
Still, making QKD systems completely secure will remain a difficult challenge for a while. As explained by fellow author Raju Valivarthi, the components used to make QKD systems never fully agree with security proofs, allowing those with the technical knowledge to gain access to secure information using "blinding attacks."
"So-called 'blinding attacks' exploit vulnerabilities of single photon detectors (SPDs) to open a side-channel, via which an eavesdropper can gain full information about the (assumed-to-be) secure key," he said.
Professor Wolfgang Tittel, the research group's leader, remained optimistic about his team's work, saying, "our experimental demonstration paves the way for MDI-QKD-based star-type quantum networks with kbps secret key rates spanning geographical distances of more than 100km."
Making quantum networks more secure may take some time, but it's an invaluable step forward. Quantum computers, as well as AI, are expected to be our best defense in cybersecurity, and they'll only remain that way if they're unable to be compromised. It's unclear when they'll be available to consumers, but expect them to change the world in radical ways once they are introduced.