News

We have a new paper out in Optics Express on our teleportation-based “heralded photon amplification” work. We demonstrate post-selection free heralded qubit amplification for Time-Bin qubits and single photon states in an all-fibre, telecom wavelength, scheme that highlights the simplicity, stability and potential for fully integrated photonic solutions. This provides a significant advance towards demonstrating device-independent quantum key distribution as well as fundamental tests of quantum…

Photodynamic therapy (PDT) is a recent technique that can help the treatment of various medical conditions, from skin and prostate cancer to certain bacterial infection. In our recent paper on Biomedical Optics Express we demonstrated that using a practical and efficient InGaAs/InP single-photon detector we developed, we are able to detect the faint luminescence signal ( at 1270 nm) from the decay of singlet-oxygen, the active molecule involved in PDT. This helped quantify the amount of…

In our recent Physical Review Letters paper we demonstrate a novel detection scheme that provides a practical way of characterising entanglement for quantum communication networks. On the theory side, we devised a new witness of entanglement that is robust as well as scalable, meaning that it can be implemented in any number of parties, i.e. complex quantum networks. Experimentally we tested our witness for two and three parties, with different losses and with different degree of entanglement.…

In our letter published in Nature Photonics we have demonstrated quantum key distribution (QKD) over 307 km. The research has also been highlighted by several local newspapers, including Tribune de Genève. This is the first time that such a distance has been achieved, whilst maintaining a quantifiable security measure of the whole protocol. That is to say, we can quantify the probability of an unwanted person learning part of the secret key. In our case, the probability of this happening was…