For those of you that weren’t at the Hackaday SuperConference, it started off with a pretty intense talk that could have been tough for anyone to follow. However, [Shanni Prutchi] presented her talk on quantum entanglement of photons in a way that is both approachable, and leaves you with plenty of hints for further study. Check it out in the video below, and join us after the break for a rundown of what she covered in her presentation.
Quantum Entanglement of Photons
[Shanni Prutchi] is studying Electrical and Computer Engineering at Rowan University and has already been published on the topics of radio astronomy and radiation measurement. But more directly connected to this talk is her co-authorship of the book Exploring Quantum Physics Through Hands-On Projects.
[Shanni] explains the current methods of identifying two entangled photons. She is not just explaining how one could conduct this experiment, she is explaining how she did conduct this experiment. First, a UV laser beam is sent through a non-linear optical crystal. On the other side, randomly polarized entangled photons are emitted. The polarization of these pairs will be forever linked, and measuring the angle of polarization of one indicates the angle of the other. It is then just a matter of identifying which photons are linked and using the entanglement for a purpose.
Quantum Teleportation and Quantum Key Distribution
The two particles have properties that are tied to each other in such a way that the quantum state of one particle exhibits an immediate correlation to its entangled particle, even when the particles are separated. Of course it is the separation of these particles that makes trait is most useful.
The first example is a form of quantum teleportation. The sender manipulates one entangled photon while the receiver measures this. The manipulation happens instantaneously despite any physical distance between the two. The particle itself doesn’t move, but in essence the entangled particle on the receiving end shows the exact same properties as the one on the transmitting end. This gives the appearance that the particle has been teleported from one place to another. [Shanni] mentions that it is actually destruction and recreation of a particle, rather than movement.
The second application she covers is Quantum Key Distribution. This is a form of Quantum Cryptography where several pairs of entangled photons are used in something of a public/private key pair. The virtue of this system is that it make it possible to immediately detect a man-in-the-middle attack. However, as [Shanni] mentions, there is current research that points to vulnerabilities in this system.
As [Shanni] works her way through school we hope to see and hear more from her; we’ll be brushing up on our physics vocab in the meantime. If you didn’t get a chance to talk to [Shanni] at SuperCon you can find her on Twitter as @shannirosa.