Physicists overcome major hurdle in quantum computing security tests
Researchers have solved a technical barrier that has limited quantum experiments for decades, making it possible to definitively prove quantum systems behave in ways classical physics cannot explain. The breakthrough matters because quantum-secure communications and computers depend on validating these quantum properties in real-world systems.
Originaltitel: High-visibility time-bin entanglement for testing chained Bell inequalities
<p>The violation of Bells inequality requires a well-designed experiment to validate the result. In experiments using energy-time and time-bin entanglement, initially proposed by Franson in 1989, there is an intrinsic loophole due to the high postselection. To obtain a violation in this type of experiment, a chained Bell inequality must be used. However, the local realism bound requires a high visibility in excess of 94.63% in the time-bin entangled state. In this work, we show how such a high visibility can be reached in order to violate a chained Bell inequality with six, eight, and ten terms.</p>