sciencehabit writes: A mini-arms race is unfolding in the supposed field of quantum radar, spurred by press reports in 2016 that China had built one — potentially threatening the ability of stealthy military aircraft to hide from conventional radars. Governments around the world have tasked physicists to look into the idea. Whereas a conventional radar searches for objects by detecting pulse…
Tag: entanglement
A quantum thermometer to measure the coldest temperatures in the universe
Physicists from Trinity College Dublin have proposed a thermometer based on quantum entanglement that can accurately measure temperatures a billion times colder than those in outer space. …
Quest for quantum Internet gets a boost with new technique for making entanglement
Traditional ways of producing entanglements, necessary for the development of any ‘quantum internet’ linking quantum computers, are not very well suited for fiber optic telecoms networks used by today’s non-quantum internet. However, researchers have come up with a new way to produce such particles that is much more compatible. …
Demonstrating entanglement through a fiber cable with high fidelity
A team of researchers from Heriot-Watt University, the Indian Institute of Technology and the University of Glasgow has demonstrated a way to transport entangled particles through a commercial fiber cable with 84.4% fidelity. In their paper published in the journal Nature Physics, the group describes using a unique attribute of entanglement to achieve such high fidelity. Andrew Forbes and Isaac Nape…
Researchers develop a tool for characterizing frequency-entangled photon pairs
Frequency-entangled photon pairs, an easily accessible type of entanglement, have been widely applied in fields like quantum-enhanced positioning and clock synchronization, and quantum spectroscopy. …
Healing an Achilles’ heel of quantum entanglement
Louisiana State University Associate Professor of Physics Mark M. Wilde and his collaborator have solved a 20-year-old problem in quantum information theory on how to calculate entanglement cost—a way to measure entanglement—in a manner that’s efficiently computable, useful, and broadly applicable in several quantum research areas. …
U.S. Hatches Plan To Build a Quantum Internet That Might Be ‘Unhackable’
U.S. officials and scientists unveiled a plan this week to pursue what they called one of the most important technological frontiers of the 21st century: building a quantum Internet. From a report: Speaking in Chicago, one of the main hubs of the work, they set goals for forging what they called a second Internet — one that would function alongside the…
Quantum cryptography keys for secure communication distributed 1,000 kilometers farther than previous attempts
The exchange of a secret key for encrypting and decrypting messages over a distance of 1,120 kilometers is reported in Nature this week. This achievement is made using entanglement-based quantum key distribution, a theoretically secure communication technique. Previous attempts to directly distribute quantum keys between two ground users under real-world conditions have reached distances of only around 100 kilometers. …
Physicists entangle 15 trillion hot atoms
Physicists set a new record by linking together a hot soup of 15 trillion atoms in a bizarre phenomenon called quantum entanglement. Source: https://www.livescience.com/physicists-entangle-15-trillion-hot-atoms.html
Connecting the quantum internet
Researchers at the Kastler Brossel Laboratory in Paris have succeeded in implementing a novel “hybrid” entanglement swapping protocol, bringing within reach the connection of disparate platforms in a future, heterogeneously structured, quantum internet. …