报告时间：6月8日 周四 下午3:00
报告题目：Quantum teleportation over fibre network towards a global quantum internet
Given a photon interacts with a member of an entangled photon pair via a so-called Bell-state measurement (BSM), its state is teleported over principally arbitrary distances onto the second member of the pair. Starting in 1997, this puzzling prediction of quantum mechanics has been demonstrated many times; however, with one very recent exception [Nature, 526, 682-686(2015)], only the photon that received the teleported state, if any, travelled far while the photons partaking in the BSM were always measured closely to where they were created. Here, using the Calgary fibre network in Canada, we report quantum teleportation from a telecommunication-wavelength photon, interacting with another telecommunication photon after both have travelled over several kilometres in beeline, onto a photon at 795 nm wavelength. This improves the distance over which teleportation takes place from 818 m to 6.2 km. Our demonstration establishes an important requirement for quantum repeater-based communications and constitutes a milestone on the path to a global quantum Internet.