Physicists Entangle Quantum Memories Across a Record-Breaking 420 Kilometers
(Wednesday August 19, 2026 @03:00AM (BeauHD)
from the promising-step-forward dept.)
- Reference: 0185045730
- News link: https://tech.slashdot.org/story/26/08/19/0133228/physicists-entangle-quantum-memories-across-a-record-breaking-420-kilometers
- Source link:
[1]alternative_right shares a report from Phys.org:
> Optical fibers are already the backbone of global communication systems. Recently, however, physicists have started to explore how their functionality could be boosted further by conveying information via entangled quantum particles -- potentially enabling instantaneous exchanges of information across vast distances. Such a system could eventually be the basis of a future 'quantum internet,' offering a level of security and computing power beyond anything possible today. In new research [2]published in Physical Review Letters , a team led by Xi-Yu Luo at the University of Science and Technology of China in Hefei has pushed that vision further than ever, [3]entangling two quantum memories across 420 kilometers (261 miles) of optical fiber -- more than four times the previous record.
[1] https://slashdot.org/~alternative_right
[2] https://journals.aps.org/prl/abstract/10.1103/ccd6-rf1s
[3] https://phys.org/news/2026-08-physicists-entangle-quantum-memories-km.html
> Optical fibers are already the backbone of global communication systems. Recently, however, physicists have started to explore how their functionality could be boosted further by conveying information via entangled quantum particles -- potentially enabling instantaneous exchanges of information across vast distances. Such a system could eventually be the basis of a future 'quantum internet,' offering a level of security and computing power beyond anything possible today. In new research [2]published in Physical Review Letters , a team led by Xi-Yu Luo at the University of Science and Technology of China in Hefei has pushed that vision further than ever, [3]entangling two quantum memories across 420 kilometers (261 miles) of optical fiber -- more than four times the previous record.
[1] https://slashdot.org/~alternative_right
[2] https://journals.aps.org/prl/abstract/10.1103/ccd6-rf1s
[3] https://phys.org/news/2026-08-physicists-entangle-quantum-memories-km.html
Disgusting summary (Score:2)
by cfalcon ( 779563 )
"potentially enabling instantaneous exchanges of information across vast distances"
NO this has nothing to do with that. This is the first slashdot post in memory that should be fucking deleted. Disgraceful.
How long did this take? (Score:2)
by Zorpheus ( 857617 )
How long did this take? As they already write, most photons are lost over such a long fiber. And quantum communication has to be done with single photons, each photon has to be measured individually. And they have to do some statistics over many photons to confirm entanglement.
Well, a PhD has about three years time ...
Once again (Score:3)
Entangled quantum particles do not allow for faster than light communication. They allow you to be sure that once you collapse the quantum state on one end, it has been or will be the same one on the other end too. The moment you entagle two states, you know they're the same (or "matching", which can also mean opposite depending on the states) without actually measuring either of them (where measuring does require destroying them).
A quantum state is like a scrach lottery ticket. You don't know if it's gonna win on lose until you scratch it and essentially invalidate it as a "playable" lottery ticket. Quantum entanglement allows you to "clone" tickets without actually scratching them, but you won't know if they're winners or losers, just that they match.
Re: (Score:2)
Yes, the ansible thing is a scifi trope, not reality. However, this is a significant extension of entanglement. Understanding things in this arena are central to breakthroughs in quantum computing.
Re: (Score:2)
detailed but clear information here:
[1]*** [researchgate.net]
[1] https://www.researchgate.net/post/Can_Quantum_Entanglement_Truly_Facilitate_Information_Exchange