Semi-device-independent full randomness amplification based on energy bounds

Understand

Quantum Bell nonlocality allows for the design of protocols that amplify the randomness of public and arbitrarily biased Santha-Vazirani sources, a classically impossible task.

• Information-theoretical security in these protocols is certified in a device-independent manner, i.e.
• solely from the observed nonlocal statistics and without any assumption about the inner-workings of the intervening devices.
• On the other hand, if one is willing to trust on a complete quantum-mechanical description of a protocol's devices, the elementary scheme in which a qubit is alternatively measured in a pair of mutually unbiased bases is, straightforwardly, a protocol for randomness amplification.