In a groundbreaking effort to create a quantum internet, scientists are exploring the fascinating world of quantum memories—devices that store delicate information on a tiny scale. These memories are vital for developing quantum networks, which promise ultra-secure communication and the ability to connect far-off quantum computers. Recently, two brilliant teams achieved an exciting milestone by entangling quantum memories in bustling urban environments, overcoming significant challenges with remarkable success.
In Boston and Cambridge, researchers connected two quantum memories over a 35-kilometer fiber loop, maintaining entanglement for an impressive duration of about a second—quite a feat in the quantum realm! They used innovative diamond-based quantum bits, cleverly entangling them via photons traveling through the fiber.
Meanwhile, in Hefei, China, another ingenious team achieved entanglement between three quantum memories spaced about 20 kilometers apart. Their creative setup involved rubidium atoms emitting photons, which were measured at a central station to establish entanglement. This required precise phase stabilization to adjust for fiber length changes due to temperature shifts, showcasing their exceptional expertise.
Both teams successfully demonstrated “heralded” entanglement, ensuring the entanglement persisted long enough for practical applications. These pioneering achievements highlight diverse and promising approaches to advancing quantum networks, paving the way for a bright future in communication technology!