Quantum Internet Getting Closer with New U.S. Army Research Lab and the University of Innsbruck Research
Army Project Brings Quantum Internet Closer to Reality
+ The U.S. Army’s Combat Capability Development’s Army Research Laboratory’s Center for Distributed Quantum Information, funded and managed by the lab’s Army Research Office, saw researchers at the University of Innsbruck achieve a record for the transfer of quantum entanglement between matter and light — a distance of 50 kilometers using fiber optic cables.
+ Entanglement is a correlation that can be created between quantum entities such as qubits. When two qubits are entangled and a measurement is made on one, it will affect the outcome of a measurement made on the other, even if that second qubit is physically far away.
“The demonstration is a major step forward for achieving large scale distributed entanglement,” said Dr. Sara Gamble, co-manager of the Army program supporting the research. “The quality of the entanglement after traveling through fiber is also high enough at the other end to meet some of the requirements for some of the most difficult quantum networking applications.”
The challenge is to transmit the photon over fiber optic cables.
+ The research team started the experiment with a calcium atom trapped in an ion trap. Using laser beams, the researchers wrote a quantum state onto the ion and simultaneously excited it to emit a photon in which quantum information is stored. As a result, the quantum states of the atom and the light particle were entangled.
+ His team therefore initially sent the light particle through a nonlinear crystal illuminated by a strong laser. The photon wavelength was converted to the optimal value for long-distance travel — the current telecommunications standard wavelength of 1,550 nanometers.
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