Scientists Transmit Quantum Messages Over 158 Miles Using Standard Network Infrastructure

[Social Media]

 

In a significant stride toward a quantum internet, scientists have successfully transmitted quantum information over 158 miles using ordinary computers and existing fiber-optic cables. This milestone marks the first time coherent quantum communication—an ultra-secure form of data transmission—has been achieved through conventional telecommunications infrastructure without the need for costly cryogenic cooling.

 

“Our equipment was running alongside the fibers that we use for regular communication literally buried underneath the roads and train stations,” explained Mirko Pittaluga, a physicist and lead author of the study published in Nature. Pittaluga and his colleagues at Toshiba Europe achieved this breakthrough by integrating largely off-the-shelf components into a setup that allowed them to relay quantum messages between the German cities of Kehl and Frankfurt via a midpoint detector in Kirchfeld. This real-world configuration demonstrates that quantum communication no longer needs to be confined to laboratory conditions.

 

 

“This is about as real-world as one could imagine,” remarked David Awschalom, a professor of physics and molecular engineering at the University of Chicago, who was not involved in the study. “It’s an impressive, quite beautiful demonstration.”

 

Unlike traditional digital data, which travels as bits valued at 0 or 1, quantum information is transmitted in qubits. Qubits can represent multiple values simultaneously, providing a more secure channel for communication. The experiment's success points toward a future where secure quantum messaging could be deployed across metropolitan areas, benefiting industries such as banking, healthcare, and government.

 

With quantum computers becoming increasingly powerful, traditional encryption methods are growing vulnerable. Sensitive online data—ranging from medical records to financial information—is currently protected by mathematical encryption keys. While these are tough for classical computers to break, quantum machines could eventually render them obsolete.

 

“Anything meaningful that’s over the internet can be tapped, recorded and saved for the next decade, and can be decrypted years later,” warned Prem Kumar, a professor of electrical and computer engineering at Northwestern University. “It’s what’s called harvest now and decrypt later.”

 

Quantum cryptography offers a solution by generating encryption keys based on the immutable laws of quantum physics rather than mathematical complexity. “The likelihood of them being able to reverse engineer a quantum key, which is the number you would need to decrypt your information, is vanishingly small,” Awschalom noted.

 

The challenge has been distributing those keys over meaningful distances. Unlike classical information, which is sent as pulses of light containing millions of photons, quantum data is carried by single photons. Detecting these photons typically requires superconducting sensors cooled to temperatures below minus 454 degrees Fahrenheit—a method that is both costly and incompatible with today’s communication networks.

 

Pittaluga’s team circumvented this limitation by employing avalanche photodiodes, inexpensive detectors that can operate at or near room temperature. These detectors had not previously been used for coherent quantum communication due to issues such as lower photon detection efficiency and susceptibility to afterpulsing—residual noise from earlier transmissions that distorts current readings.

 

To combat this, the researchers deployed two sets of detectors: one to capture the signal and the other to filter out environmental noise. This innovative setup paved the way for a more affordable and scalable approach to quantum messaging.

 

Pittaluga believes this development brings society a step closer to the realization of a quantum internet. “The goal of this setup is to bring us one step closer to a quantum internet, with incredibly secure information,” he said.

 

Despite its promise, quantum communication still faces hurdles in cost and complexity when compared to traditional encryption systems. Yet optimism remains. “My personal view is that we’ll be seeing quantum encryption of data sets and metropolitan scale quantum networks within a decade,” said Awschalom.

 

  Adpated by ASEAN Now from The Washington Post  2025-04-25

 

 

[Purdey]

Got a bad feeling the CIA will stop this development.

[WDSmart]

I like this a lot better than sending satellites out into space. Radio waves are not litter.