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Modern computing and communication technologies such as supercomputers and the Internet are based on optically connected networks of microwave-frequency information processors. An analogous architecture has been proposed for quantum networks, using optical photons to distribute entanglement between remote superconducting quantum processors. Here we report a step towards such a network by observing non-classical correlations between photons in an optical link and a superconducting quantum device. We generate these states of light through a spontaneous parametric down-conversion process in a chip-scale piezo-optomechanical transducer, and we measure a microwave–optical cross-correlation exceeding the Cauchy–Schwarz classical bound for thermal states. As further evidence of the non-classical character of the microwave–optical photon pairs, we observe antibunching in the microwave state conditioned on detection of an optical photon. Such a transducer can be readily connected to an independent superconducting qubit module and serve as a key building block for optical quantum networks of microwave-frequency qubits. 

Abstract High-dimensional quantum entanglement is a cornerstone for advanced technology enabling large-scale noise-tolerant quantum systems, fault-tolerant quantum computing, and distributed quantum networks. The recently developed biphoton frequency comb (BFC) provides a powerful platform for high-dimensional quantum information processing in its spectral and temporal quantum modes. Here we propose and generate a singly-filtered high-dimensional BFC via spontaneous parametric down-conversion by spectrally shaping only the signal photons with a Fabry-Pérot cavity. High-dimensional energy-time entanglement is verified through Franson-interference recurrences and temporal correlation with low-jitter detectors. Frequency- and temporal- entanglement of our singly-filtered BFC is then quantified by Schmidt mode decomposition. Subsequently, we distribute the high-dimensional singly-filtered BFC state over a 10 km fiber link with a post-distribution time-bin dimension lower bounded to be at least 168. Our demonstrations of high-dimensional entanglement and entanglement distribution show the singly-filtered quantum frequency comb’s capability for high-efficiency quantum information processing and high-capacity quantum networks. 

Pettalidae is a family of mite harvestmen that inhabits the former circum-Antarctic Gondwanan terranes, including southern South America, South Africa, Madagascar, Sri Lanka, Australia and New Zealand. Australia is home to two pettalid genera, Austropurcellia, in northern New South Wales and Queensland, and Karripurcellia, in Western Australia, until now showing a large distributional gap between these two parts of the Australian continent. Here we report specimens of a new pettalid from South Australia, Archaeopurcellia eureka, gen. et sp. nov., closing this distributional gap of Australian pettalids. Phylogenetic analyses using traditional Sanger markers as well as ultra-conserved elements (UCEs) reveal that the new genus is related to the Chilean Chileogovea, instead of any of the other East Gondwanan genera. This relationship of an Australian species to a South American clade can be explained by the Antarctic land bridge between these two terranes, a connection that was maintained with Australia until 45 Ma. The UCE dataset also shows the promise of using museum specimens to resolve relationships within Pettalidae and Cyphophthalmi. ZooBank: urn:lsid:zoobank.org:pub:9B57A054-30D8-4412-99A2-6191CBD3BD7E 

Abstract Decisions related to the production of lithic technology involve landscape-scale patterns of resource acquisition and transport that are not observable in assemblages from any one single site. In this study, we describe the stone artifacts from a discrete cluster of stone artifacts assigned to the Robberg technocomplex (22-16 ka) at the open-air locality of Uitspankraal 9 (UPK9), which is located near two major sources of toolstone in the Doring River catchment of Western Cape, South Africa.OSLdating of the underlying sediment unit provides aterminus post quemage of 27.5 ± 2.1 ka for the assemblage. Comparison of near-source artifact reduction atUPK9 with data from three rock shelter assemblages within the Doring watershed – Putslaagte 8 (PL8), Klipfonteinrand Rock Shelter (KFR), and Mertenhof Rock Shelter (MRS) – suggests that “gearing-up” with cores and blanks occurred along the river in anticipation of transport into the wider catchment area. The results reveal an integrated system of technological supply in which raw materials from different sources were acquired, reduced, and transported in different ways throughout the Doring River region. 

We demonstrate a technique for measuring the full-speed performance of integrated modulators from ultraweak surface-coupled and scattered light. This can enable rapid characterization of unpackaged, high-speed wafer-scale integrated photonics without test ports or special fabrication.