University of Chicago's Breakthrough in Quantum Communication Extends Distances to 2000 Kilometers

Researchers at the University of Chicago have achieved a significant breakthrough in quantum communication by developing a novel crystal-growth technique that dramatically enhances quantum coherence times. This advancement could extend quantum communication distances from a few kilometers to approximately 2,000 kilometers, bringing the concept of a global quantum internet closer to reality.

Quantum communication relies on the principles of quantum mechanics to transmit information securely. A major challenge in this field has been maintaining quantum coherence over long distances, as coherence times are typically limited to fractions of a millisecond, restricting communication to a few kilometers. Extending coherence times is crucial for developing a global quantum internet.

The research team, led by Assistant Professor Tian Zhong at the University of Chicago's Pritzker School of Molecular Engineering, employed a technique called molecular-beam epitaxy (MBE) to construct rare-earth-doped crystals atom by atom. This method significantly improved material purity and coherence times. Specifically, the coherence time of individual erbium atoms was increased from 0.1 milliseconds to over 10 milliseconds, with some experiments achieving 24 milliseconds. Under ideal conditions, this improvement could enable quantum communication over distances up to 4,000 kilometers.

Traditional crystal growth methods, such as the Czochralski process, involve melting and slowly cooling materials to form crystals. While effective for many applications, this approach can introduce impurities that limit quantum coherence. In contrast, MBE allows for precise control over the crystal structure at the atomic level, resulting in materials with unprecedented purity and extended coherence times.

This advancement addresses a significant hurdle in quantum networking: the limited distance over which quantum information can be reliably transmitted. By extending coherence times, the research paves the way for connecting quantum computers across continents, bringing the vision of a global quantum internet closer to reality. Such a network could revolutionize fields like secure communication, distributed computing, and precision sensing.

Assistant Professor Tian Zhong emphasized the significance of this development, stating, "For the first time, the technology for building a global-scale quantum internet is within reach."

The University of Chicago has been at the forefront of quantum research. In November 2025, the university partnered with IonQ to advance quantum science and engineering, aiming to develop technologies like powerful quantum computers and ultra-secure quantum communication networks. Additionally, in October 2025, UChicago researchers developed molecular qubits compatible with standard telecommunications networks, a key step toward a future quantum internet.

The ability to transmit quantum information over thousands of kilometers could lead to ultra-secure communication channels, immune to eavesdropping due to the principles of quantum mechanics. This has profound implications for national security, financial transactions, and personal privacy. Furthermore, a global quantum internet could enable distributed quantum computing, allowing complex computations to be performed more efficiently by leveraging interconnected quantum processors.

The University of Chicago's recent breakthrough in extending quantum coherence times represents a pivotal step toward realizing a global quantum internet. By employing advanced crystal-growth techniques, researchers have overcome a major limitation in quantum communication, opening new avenues for secure, long-distance quantum information transfer.