A team of researchers from the Technion – Israel Institute of Technology has made a major breakthrough in quantum physics.
They’ve discovered a brand-new type of quantum entanglement involving the total angular momentum of photons—particles of light—inside extremely tiny structures.
This discovery could help shrink quantum devices in the future, making technologies like quantum computers and communication systems much smaller and more powerful.
Quantum entanglement is a strange but proven idea in physics. It was first described in 1935 by Albert Einstein and his colleagues Boris Podolsky and Nathan Rosen, in what became known as the EPR paper.
They showed that two particles could be linked in such a way that if you measured one, you would instantly know something about the other—even if they were far apart.
Einstein himself found this idea unsettling and called it “spooky action at a distance.”
Decades later, Technion professor Asher Peres helped show that this odd behavior could actually be useful.
With other scientists, he developed the idea of quantum teleportation, where information could be passed invisibly between entangled particles.
This became the foundation of quantum communication, which is expected to transform secure data transfer in the future.
Entanglement has since been shown to work for many different types of particles, including photons. Photons can be entangled based on features like the direction they travel, their color (frequency), or the direction of their electric field.
They can also be entangled by how they spin—something called angular momentum. This is similar to how Earth both spins on its axis and orbits around the sun.
Until now, scientists thought of a photon’s angular momentum as two separate things: spin and orbit. But when photons are squeezed into incredibly small spaces—smaller than the length of the light wave itself—these properties combine into one: total angular momentum.
This situation appears in the field of nanophotonics, which deals with light at the nanoscale (about a thousand times thinner than a human hair).
So why do researchers want to trap light in such tiny spaces? One reason is miniaturization—making devices smaller, like what happened with electronic circuits. Another reason is to increase the way light interacts with materials, opening up new possibilities for manipulating light that aren’t possible at larger scales.
In their new study, published in the journal Nature, Technion researchers led by Ph.D. student Amit Kam and Dr. Shai Tsesses showed for the first time that photons in these nanoscale systems can become entangled not by their usual properties, but only through their total angular momentum.
They carefully mapped the photons’ states and showed that pairs of them were connected in this new way.
This marks the first time in over 20 years that a new form of quantum entanglement has been discovered. It could lead to exciting new tools for building smaller, faster, and more efficient quantum technologies, helping bring the power of quantum computing and communication into even tinier spaces.
Source: KSR.
