Llum i comunicació, la revolució quàntica

The laws of quantum physics guarantee the security of secret data communications. Quantum cryptography, or more specifically, QKD, has an advantage over classical cryptography: it’s not possible for an intruder to know the key that encodes the message without being discovered, thanks to the uncertainty principle of Heisenberg, quantum superposition and quantum non-cloning theorem. In the future, the birth of the first functional quantum computers will force us to substitute our classical cryptography for quantum cryptography to keep safe communications.
Cryptography techniques rely on chains of random numbers used to generate safe encryption keys. Random numbers can be predicted if the behaviour of generator algorithms is known. When the generators are quantum, their performance can’t be predicted in any way, therefore they can be used for totally safe communications.
In this work we have been able, thanks to the opportunity given by ICFO, to perform some experiments with lasers, optical fibers and quantum random number generators and to get to know the importance of quantum mechanics for the future of safe communications.