Yu Cai

The National Quantum-Safe Network (NQSN) in Singapore is a nationwide collaborative platform and a field-deployed test-bed aimed at demonstrating quantum-safe cryptography solutions. NQSN links up academic, public and private members, targets trials for quantum key distribution (QKD) network with different QKD protocols, post-quantum cryptography (PQC) and classical symmetric key technologies.

Quantum physics provides some natural ways to generate genuine randomness, however, the generation of certifiable randomness still meets various theoretical and technical challenges. Recently, a work on a source device independent protocol was proposed, where the measurement apparatus is fully trusted and no assumption about the incoming light source is made. Here, we experimentally implement and verify a source device independent quantum random number generator (SDI-QRNG), built with off-the-shelf optical and electronic components. Furthermore, a series of quantum attacks were performed to evaluate the security and implementation vulnerability of the SDI-QRNG.

We give an explicit construction for classes of quantum states of qubits, whose complexity grows super-polynomially in the number of qubits, and discuss the properties of these states. The complexity measure considered is the tree size of a quantum state which is in principle computable and is closely related to the size of a multi-linear formula. Several conjectures and partially known relations to entanglement and quantum computational power will be discussed. Based on arXiv:1303.4843.