Phys.org December 28, 2022 There has been exciting recent progress in satellite-based quantum communications and quantum repeaters, but a lack of suitable single-photon sources has hampered further advances. The visibility of quantum interference between independent QDs rarely went beyond the classical limit of 50%, and the distances were limited from a few meters to kilometers. An international team of researchers (China, Germany) has shown quantum interference between two single photons from independent QDs separated by a 302 km optical fiber. The single photons were generated from resonantly driven single QDs deterministically coupled to microcavities. Quantum frequency conversions were used to […]
Tag Archives: Single photon sources
Scientists Find Yet Another Way to Get Qubits Working at Room Temperature
Science Alert March 22, 2020 Defect-based quantum systems are often complicated by charge-state instabilities and interference by phonons, which can diminish spin-initialization fidelities and limit room-temperature operation. An international team of researchers (Hungary, Sweden, USA – Argonne National Laboratory, University of Chicago, IBM, Russia) has identified a pathway around these drawbacks by showing that an engineered quantum well can stabilize the charge state of a qubit. Using density-functional theory and experimental synchrotron X-ray diffraction studies they constructed a model for previously unattributed point defect centers in silicon carbide as a near-stacking fault axial divacancy and showed how this model explains […]