Posted on 01/17/2021 8:02:34 AM PST by BenLurkin
Quantum communication promises fully secure message sharing. For example, two users could exchange encrypted messages using “entangled” photons, pairs of particles with a unique quantum-mechanical relationship. For every pair, one photon would be sent to each of the users, who would be alerted to any eavesdropping by a loss of entanglement between the photons. One of the most common methods for sending such quantum encrypted messages relies on optical fibers... But in fibers, a large fraction of the photons scatter before reaching their destination....
Small drones carrying optical equipment could provide a flexible solution that could link multiple users in a quantum network. “Drones can be deployed for a mobile quantum connection at any given time and location when necessary,” says Zhenda Xie from Nanjing University in China. Unlike a fixed tower, drones can also move around to avoid pollution or fog.
Xie and colleagues reported a quantum link using a single octocopter-style drone. The drone generated pairs of infrared photons whose polarization orientations were entangled. ... To collect the incoming photons, each station was equipped with a telescope having a 26-mm-wide aperture and a single-photon detector.
However, a major challenge to this form of optical communication comes from diffraction. As each photon propagates, its wave front spreads out, like the beam from a flashlight. If this spreading makes the wave front larger than the telescope aperture, the photon will have little chance of being collected....
To increase station separation, the team has now added a second drone that acts as a relay...This drone collects photons from the first drone and collimates them through an optical fiber. This process reshapes the photon wave fronts—similar to what a focusing lens does...
(Excerpt) Read more at physics.aps.org ...
Quantum Computing will change everything—China is ahead of us on this, BTW.
We gave them technology (Clinton/Loral) and they ran with it. Why is Clinton not in Jail?
Think about Drones in the context of the Inauguration...
Just sayin’
“Quantum Computing will change everything—China is ahead of us on this, BTW.”
Maybe, but they are way behind us in important sciences like LGBTXYZ rights, systemic racism, how to use the correct pronouns, etc.
They don’t stand a chance!
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