China’s Quantum Breakthrough: Building a Secure Global Quantum Network

• Quantum precision measurement: Ultra-high-accuracy information sensing
• Quantum communication: Transmission that cannot be hacked without detection
• Quantum computing: Processing speeds that dwarf classical systems

China just pulled off something that’s been on the quantum computing wishlist for decades.

Researchers at the University of Science and Technology of China (Zhongguo Kexue Jishu Daxue 中国科学技术大学) led by Pan Jianwei (Pan Jianwei 潘建伟) have cracked a fundamental problem that’s been blocking quantum networks from going mainstream: how to send quantum information reliably over long distances.

The implications are massive.

We’re talking about unhackable communication networks, quantum computers working together across continents, and a fundamentally new way to process information at scales we can’t achieve today.

Here’s what happened, why it matters, and what comes next in the race for quantum network dominance.

---

Two Major Breakthroughs Hit at Once

In February 2026, two separate research papers dropped that signal China’s quantum advantage is accelerating.

Team 1: The Quantum Repeater Breakthrough

Pan Jianwei’s group at USTC partnered with the Jinan Institute of Quantum Technology (Jinan Liangzi Jishu Yanjiuyuan 济南量子技术研究院), the Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences (Zhongguo Kexueyuan Shanghai Weixitong yu Xinxi Jishu Yanjiusuo 中国科学院上海微系统与信息技术研究所), the University of Hong Kong, and Tsinghua University (Qinghua Daxue 清华大学) to develop something that’s been theoretically possible but practically impossible: scalable quantum repeaters that actually work.

This research was published in Nature on February 3, 2026.

Team 2: The Long-Distance Entanglement Win

A separate team including researchers Bao Xiaohui (Bao Xiaohui 包小辉), Xu Feihu (Xu Feihu 徐飞虎), and Zhang Qiang (Zhang Qiang 张强) partnered with the National University of Singapore and the University of Waterloo, Canada to push Device-Independent Quantum Key Distribution (DI-QKD) beyond 100 kilometers.

This paper hit Science on February 6, 2026.

Together, these breakthroughs represent the first practical demonstration that quantum networks can scale beyond laboratory settings.

---

Why This Matters: The Quantum Network Vision

Before diving into the technical details, let’s talk about what quantum networks are actually supposed to do.

The end goal isn’t just one quantum computer in one lab—it’s a connected ecosystem where quantum technology handles three critical functions:

• Quantum precision measurement for ultra-high-accuracy information sensing
• Quantum communication for transmission that literally cannot be hacked without detection
• Quantum computing for processing speeds that dwarf classical systems

The backbone holding all of this together? Long-distance, reliable quantum entanglement distribution.

Once you have stable entanglement between distant nodes, you unlock two killer applications:

• Quantum Key Distribution (QKD): Share encryption keys with mathematically proven unhackability
• Quantum teleportation: Transfer quantum information between computers without physically moving it

Sound sci-fi? It’s not. But there’s been a massive roadblock preventing this from working at scale.

---

The Fundamental Problem: Fiber Loss Kills Everything

Here’s where it gets sobering.

Light traveling through optical fiber doesn’t just degrade—it collapses exponentially.

After traveling 1,000 kilometers through standard fiber, a light signal weakens to 10⁻²⁰ (one sextillionth) of its original strength.

To put that in perspective:

• Even with a source pumping out 10 billion entangled pairs per second
• You’d receive on average just one pair after waiting 300 years

That’s not a network. That’s a cruel joke.

This exponential loss is the single biggest obstacle preventing quantum networks from becoming reality at useful distances.

If you can’t solve this, quantum networks stay in the lab forever.

---

Meet the Solution: Quantum Repeaters

The theoretical answer has existed since the late 1990s: quantum repeaters.

The concept is elegant.

Instead of trying to send entanglement across 1,000 kilometers directly, you break it into segments. Set up repeater stations every 100 kilometers along the fiber line.

Here’s how it works:

• Create entanglement between adjacent stations (Station A ↔ B, then B ↔ C, etc.)
• Use a process called “entanglement swapping” to link them together
• Effectively distribute entanglement across the entire 1,000-kilometer span

The efficiency gains are staggering.

With the same 10 billion pairs-per-second emission rate:

• Without repeaters: 1 pair every 300 years
• With repeaters: 100 million pairs per second

That’s a one quintillion times efficiency improvement.

Theoretically perfect. Practically? It’s been a nightmare.

---

The 30-Year Problem Nobody Could Solve

Pan Jianwei first proved that quantum entanglement could be connected back in 1998—nearly 30 years ago.

But for three decades, one brutal technical reality blocked progress: the entanglement would disappear before you could create the next one.

Think of it like trying to build a chain where each link evaporates the moment you start forging the next one.

You can’t scale something that won’t stay stable long enough to work with.

The entanglement would simply “decay”—vanish into quantum noise—before the system had time to generate fresh entanglement for the next stage.

It was a catch-22 that seemed unsolvable.

---

How USTC Finally Cracked It

Pan Jianwei’s team attacked the problem from three angles simultaneously:

1. Long-lived quantum memory

• Developed trapped-ion quantum memory that could hold information far longer than previous attempts

2. Better ion-photon interfaces

• Created high-efficiency communication channels between ions and photons (light particles)

3. Improved entanglement protocols

• Engineered high-fidelity single-photon entanglement generation

The result: an entanglement lifetime of 550 milliseconds.

That might not sound like much, but it’s the magic number.

The team needed 450 milliseconds to establish the next entanglement.

So for the first time, they had enough stability window to create the next connection before the previous one decayed.

The dominoes could finally fall in sequence instead of vanishing into the void.

This achievement completes the first practical, scalable quantum repeater module.

Not a proof of concept. Not a demonstration. A working module that can be replicated and extended.

---

The “Holy Grail” Moment: 100km Device-Independent QKD

While quantum repeaters solve the distance problem, the second breakthrough tackles something even more ambitious: unhackable communication that works even if you can’t trust your own hardware.

Traditional Quantum Key Distribution requires you to precisely calibrate and trust your devices.

But what if your hardware has been subtly compromised? What if there’s a backdoor in the firmware? What if someone physically tampered with the equipment?

Device-Independent Quantum Key Distribution (DI-QKD) eliminates that vulnerability entirely.

Here’s the magic: security is guaranteed regardless of whether the quantum devices are trustworthy or not, as long as two conditions are met:

• High-quality entanglement exists between the two endpoints
• A mathematical test (Bell inequality violation) can be verified with zero loopholes

If both conditions hold, security is mathematically proven. Even if your devices are completely compromised.

Gilles Brassard, who literally invented quantum cryptography and won the 2018 Wolf Prize for it, called DI-QKD the “Holy Grail” that cryptographers have searched for a thousand years.

It’s not hyperbole. This is the ultimate security primitive.

But there’s a catch: until now, DI-QKD only worked at distances of a few meters to a few hundred meters maximum.

The Bao/Xu/Zhang team just shattered that limitation.

---

The Numbers: Breaking the 100km Barrier

Using the scalable repeater technology developed by Pan’s team, the second research group created high-fidelity entanglement between two Rubidium atoms across fiber links up to 100 kilometers.

Here are the critical metrics:

• Fidelity maintained above 90% over the full 100-kilometer distance
• Successfully completed DI-QKD over an 11-kilometer link with strict security proofs—a 3,000x improvement over previous results
• Demonstrated feasibility for key generation over 100 kilometers—more than a 100x improvement over prior international standards

Let that sink in.

Previous DI-QKD demonstrations were limited to the scale of a lab building.

Now it’s working across city-to-city distances.

This takes DI-QKD from “cool physics experiment” to “potentially practical security infrastructure.”

---

What This Means for the Quantum Internet

These two breakthroughs work together to solve the two critical bottlenecks that prevented quantum networks from scaling:

Problem 1: Can you distribute entanglement over long distances?

• ✓ Solved by scalable quantum repeater modules with 550ms entanglement lifetime

Problem 2: Can you use that entanglement for practical, unhackable communication?

• ✓ Solved by pushing DI-QKD from meters to 100+ kilometers

For the first time, fiber-optic quantum networks are moving from theoretical possibility to engineering challenge.

The physics works. The systems work. The distances work.

What’s left is scaling, integration, and turning lab prototypes into production infrastructure.

---

Context: China’s Growing Quantum Advantage

This isn’t China’s first quantum milestone.

The nation launched the “Micius” (Mozi 号 墨子号) quantum satellite and has been steadily pushing quantum communication technology forward while most Western countries treated it as a distant research problem.

These new breakthroughs represent the next layer of that strategy: moving from satellite-based quantum communication to fiber-based networks that can integrate with existing telecommunications infrastructure.

Fiber networks are more practical, more scalable, and easier to harden than satellite links.

By solving the repeater problem, China is positioning itself to build a quantum internet backbone before most other countries even have a serious deployment strategy.

---

The Support Behind the Scenes

These aren’t scrappy startup vibes—this is state-level commitment.

The research was funded by:

• National Key R&D Program of China
• National Natural Science Foundation of China
• Chinese Academy of Sciences
• Provincial and local governments in Anhui and Shandong

This tells you something important: quantum networks aren’t a nice-to-have for China’s leadership—they’re a strategic priority.

---

The Bottom Line on Quantum Network Breakthroughs

China just moved the quantum internet from science fiction to engineering reality.

Two fundamental problems that blocked deployment for 30 years got solved in the same month.

Scalable quantum repeaters work. Long-distance unhackable communication works. The distances are practical.

The race for quantum network dominance isn’t theoretical anymore—it’s about who can turn these breakthroughs into deployed infrastructure first.

And right now, China is several laps ahead.

---

References

• China’s Quantum Tech Breakthrough – Cailian Press
• Latest Research Progress – University of Science and Technology of China
• Scalable Quantum Repeater Node – Nature
• Device-Independent Quantum Key Distribution Over 100km – Science