Cross-Verification of Independent Quantum Devices

Funding

The authors thank Sam Ferracin for helpful comments on the manuscript. T. M., R. B., P. S., M. R. gratefully acknowledge support by the Austrian Science Fund (FWF), through the SFB FoQuS (FWF Project No. F40) and SFB BeyondC (FWF Project No. F7109), by the EU H2020-FETFLAG-2018-03 under Grant Agreement No. 820495, by the U.S. Army Research Office (ARO) through Grant No. W911NF-14-1-0103, and by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), via the U.S. ARO Grant No. W911NF-16-10070. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 801110 and the Austrian Federal Ministry of Education, Science and Research (BMBWF). P. W. acknowledges support from the research platform TURIS, the Austrian Science Fund (FWF) through the Doctoral Programme CoQuS (No. W1210-4), BeyondC (F7113) and NaMuG (P30067-N36), the U.S. Air Force Office of Scientific Research via QAT4SECOMP (FA238617-1-4011), the European Commission via High Dimensional Quantum Photonic Platform Projects (HiPhoP) (No. 731473), and Red Bull GmbH. J. F. F. acknowledges support from Singapore's Ministry of Education, National Research Foundation (ANR-NRF Grant No. NRF2017-NRF-ANR004), and the U.S. Air Force Office of Scientific Research (AOARD Grant No. FA2386-18-1-4003).