For decades, scientists thought unbreakable quantum encryption required flawless light sources, a nearly impossible feat. But a team has flipped the script using tiny engineered “quantum dots” and clever new protocols.
By making imperfect light behave more securely, they proved that encrypted messages can travel farther and more safely than ever before. Real-world tests have shown that their method outperforms even the best current systems, bringing practical, affordable quantum-safe communication a significant step closer.
Breakthrough in Quantum Encryption
A team of physicists has made a breakthrough that could bring secure quantum communication closer to everyday use — without needing flawless hardware.
The research, led by PhD students Yuval Bloom and Yoad Ordan, under the guidance of Professor Ronen Rapaport from the Racah Institute of Physics at Hebrew University in collaboration with researchers from Los-Alamos National Labs, and published in PRX Quantum, introduces a new practical approach that significantly improve how we send quantum encrypted information using light particles — even when using imperfect equipment.
Cracking a 40-Year-Old Challenge
For four decades, the holy grail of quantum key distribution (QKD) — the science of creating unbreakable encryption using quantum mechanics — has hinged on one elusive requirement: perfectly engineered single-photon sources. These are tiny light sources that can emit one particle of light (photon) at a time. But in practice, building such devices with absolute precision has proven extremely difficult and expensive.
To work around that, the field has relied heavily on lasers, which are easier to produce but not ideal. These lasers send faint pulses of light that contain a small, but unpredictable, number of photons — a compromise that limits both security and the distance over which data can be safely transmitted, as a smart eavesdropper can “steal” the information bits that are encoded simultaneously on more than one photon.
A Better Way with Imperfect Tools
Bloom, Ordan, and their team flipped the script. Instead of waiting for perfect photon sources, they developed two new protocols that work with what we have now — sub-Poissonian photon sources based on quantum dots, which are tiny semiconductor particles that behave like artificial atoms.
By dynamically engineering the optical behavior of these quantum dots and pairing them with nanoantennas, the team was able to tweak how the photons are emitted. This fine-tuning allowed them to suggest and demonstrate two advanced encryption strategies:
- A truncated decoy state protocol: A new version of a widely used quantum encryption approach, tailored for imperfect single photon sources, that weeds out potential hacking attempts due to multi-photon events.
- A heralded purification protocol: A new method that dramatically improves signal security by “filtering” the excess photons in real time, ensuring that only true single photon bits are recorded.
In simulations and lab experiments, these techniques outperformed even the best versions of traditional laser-based QKD methods — extending the distance over which a secure key can be exchanged by more than 3 decibels, a substantial leap in the field.
Real-World Test of Quantum Networks
To prove it wasn’t just theory, the team built a real-world quantum communication setup using a room-temperature quantum dot source. They ran their new reinforced version of the well-known BB84 encryption protocol — the backbone of many quantum key distribution systems — and showed that their approach was not only feasible but superior to existing technologies.
What’s more, their approach is compatible with a wide range of quantum light sources, potentially lowering the cost and technical barriers to deploying quantum-secure communication on a large scale.
Toward Affordable Quantum-Secure Communication
“This is a significant step toward practical, accessible quantum encryption,” said Professor Rapaport. “It shows that we don’t need perfect hardware to get exceptional performance — we just need to be smarter about how we use what we have.”
Co-Lead author Yuval Bloom added, “We hope this work helps open the door to real-world quantum networks that are both secure and affordable. The cool thing is that we don’t have to wait; it can be implemented with what we already have in many labs worldwide.”
Reference: “Decoy-State and Purification Protocols for Superior Quantum Key Distribution with Imperfect Quantum-Dot-Based Single-Photon Sources: Theory and Experiment” by Yuval Bloom, Yoad Ordan, Tamar Levin, Kfir Sulimany, Eric G. Bowes, Jennifer A. Hollingsworth and Ronen Rapaport, 21 August 2025, PRX Quantum.
DOI: 10.1103/7fdd-m92n
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8 Comments
What’s more, their approach is compatible with a wide range of quantum light sources, potentially lowering the cost and technical barriers to deploying quantum-secure communication on a large scale.
VERY GOOD.
Please ask the researchers to think deeply:
1. How do you understand the quantum light sources?
2. What are the quantum light sources?
3. What are the quantum?
4. Where does quantum come from?
5. Where does the singularity come from?
6. Where does the energy of the singularity explosion come from?
7. Isn’t space everywhere?
8. Where do things in space come from?
9. Why does physics today ignore the ubiquity of space and instead search for imaginary God particles everywhere?
10. Isn’t space a physical entity?
11. As a physical entity, what physical properties should space possess?
12. If the space does not have physical entity properties, please inform the public where the physics experiment was conducted?
An entire generation has been severely misled, poisoned and fooled by so-called peer-reviewed publications. In today’s physics, the so-called peer-reviewed journals—including Physical Review Letters, Nature, Science, and others—stubbornly insist on and promote the following:
1. Even though θ and τ particles exhibit differences in experiments, physics can claim they are the same particle. This is science.
2. Even though topological vortices and antivortices have identical structures and opposite rotational directions, physics can define their structures and directions as entirely different. This is science.
3. Even though two sets of cobalt-60 rotate in opposite directions and experiments reveal asymmetry, physics can still define them as mirror images of each other. This is science.
4. Even though vortex structures are ubiquitous—from cosmic accretion disks to particle spins—physics must insist that vortex structures do not exist and require verification. Only the particles that like God, Demonic, or Angelic are the most fundamental structures of the universe. This is science.
5. Even though everything occupies space and maintains its existence in time, physics must still debate and insist on whether space exists and whether time is a figment of the human mind. This is science.
6. Even though space, with its non-stick, incompressible, and isotropic characteristics, provides a solid foundation for the development of physics, physics must still insist that the ideal fluid properties of space do not exist. This is science.
And so on.
The so-called peer-reviewed journals—including Physical Review Letters, Nature, Science, and others openly define differences as sameness, sameness as differences, existence as nonexistence, and nonexistence as existence—all while deceiving and fooling the public with so-called “impact factors (IF),” never knowing what shame is.
The universe is not a God, nor is it merely Particles. Moreover, it is not Algebra, Formulas, or Fractions. The universe is the superposition, deflection, entanglement, and locking of spacetime vortex geometries, the interaction and balance of topological vortices and their fractal structures. Topological invariants are the identical intrinsic properties between two isomorphic topological spaces. Different civilizations may create distinct mathematical codes or tools to describe the universality and specificity of these topological invariants under different physical laws.
Topology provides stability blueprints, but specific physics (spatial features, gravitational collapse, fluid viscosity, quantum measurement) dictates vortex generation, evolution, and decay. If researchers are interested in this, please visit https://zhuanlan.zhihu.com/p/1933484562941457487 and https://zhuanlan.zhihu.com/p/1925124100134790589.
Crazy much?
Broken clocks are right twice a day, that’s science. Lol
Shut up. Nerd.
It is very misleading to refer to this as quantum ENCRYPTION. The encryption algorithm itself (probably a symmetric algorithm like AES) has nothing to do with quantum physics. The quantum part (which is important) is only about how the encryption keys are sent from one party to another.
@Todd … In a paper I wrote, I included a section containing quantum encryption. If you’d be willing to view it, I’d appreciate your take on it.
@whoever wrote the 12 experimental questions and 6 scientific protocols …. I’m not certain I could have said it any better myself. Aside from all the facts you’ve pointed out above, they have disassociated themselves to the point inaccessibility. They act as though they wish to know answers to problems but instead make up some kind of placeholder to fit their failing model instead of searching for the fundamental answer. Don’t even get me started on their over-exstensive use of time as a coordinate. Don’t get me wrong, it works great for answers that are relative but again does nothing for fundamental truths.
My name’s really not, 12.