Scientist Set 'Quantum' Record, Entangle 3,000 Atoms with One Photon
MIT Researchers have managed to entangle as many as 3,000 atoms with just one photon.
According to Discovery News, the entanglement is a record of sorts as previous efforts managed to entangle just a few hundred atoms. Entanglement is a quantum phenomenon where two unconnected fundamental particles, like atoms, can appear to be connected and influence each other even when separate by large distances. The latest achievement is expected to pave the way for improved atomic clocks.
"You can make the argument that a single photon cannot possibly change the state of 3,000 atoms, but this one photon does - it builds up correlations that you didn't have before. We have basically opened up a new class of entangled states we can make, but there are many more new classes to be explored," said Vladan Vuletic, the paper's senior author.
To achieve mass entanglement, Vuletic and his team cooled rubidium atoms to just a few degrees above the absolute zero, the lowest possible temperature, centered between two mirrors. They then transmitted weak laser, with just a single photon that oscillated between the mirrors. A weak laser was used to prevent noise that quantum measurements cause. Interaction of atoms with photon can cause subtle changes in its polarization, causing entanglement.
Entanglement with larger number of atoms can be used to produce highly accurate atomic clocks that can be used in GPS. The phenomenon can also be instrumental in quantum computing and quantum encryption.
