Another Step In Quantum Computing: A Functional Interconnect
New submitter Gennerik writes: According to a recent article in the MIT Technology Review, a team of international physicists have been able to create a quantum computing interconnect. The interconnect, which is used to connect separate silicon photonic chips, has the important feature of preserving entanglement. This marks a vital step in creating quantum computers that don't have to work in isolation. According to the article, the trick that
The trick that [University of Bristol Researcher Mark Thomson] and pals have perfected is to convert the path-entanglement into a different kind of entanglement, in this case involving polarization. They do this by allowing the path-entangled photons to interfere with newly created photons in a way that causes them to become polarized. This also entangles the newly created photons, which pass into the optical fiber and travel to the second silicon photonic chip.
No. That's not how entanglement works. A better way of thinking about entanglement is imagining two fair coins that can be any distance apart and the first time you flip them, you are guaranteed that they'll either both be heads or both be tails. This isn't a perfect description, but this is close enough. If one wants to be mathematically rigorous then we'd say that two particles are entangled if we cannot describe their combined state simply as the tensor product of the state of each one https://en.wikipedia.org/wiki/Quantum_entanglement#Quantum_mechanical_framework. If you want to read a good introduction to a lot of these issues, I recommend Scott Aaronson's "Quantum Computing Since Democritus" which is essentially aimed as an introduction to quantum computing for non-experts with a some math background (essentially assumes is ok with basic linear algebra and basic calculus). Scott is an absolutely fantastic writer.