Relaxing assumptions in Device-independent quantum cryptography

Device-independent (DI) quantum cryptography aims to provide information-theoretic security with minimal trust in, or characterisation of, the underlying quantum devices. A major challenge in DI protocols is the requirement of various initial resources, which can be difficult to justify. For example, randomness expansion and quantum key distribution (QKD) requires the honest parties to have additional near-perfect random bits (a seed) that is independent of the protocol. In this talk, I will present a number of techniques that allow for the relaxation of this resource. I will discuss randomness extractors which allow for a shorter and/or lower quality seed and introduce our software library Cryptomite, which provides (numerically precise and) efficiently implemented extractors that are easy to use. I will then introduce a new approach to randomness extraction which is deterministic (i.e. allows eliminating the seed altogether). Finally, I will show how some of these features can be used to construct improved DI protocols and end with some open problems