@article {Elben2020a,
	title = {Cross-Platform Verification of Intermediate Scale Quantum Devices},
	journal = {Physical Review Letters},
	volume = {124},
	year = {2020},
	month = {jan},
	pages = {010504},
	publisher = {American Physical Society},
	abstract = {We describe a protocol for cross-platform verification of quantum simulators and quantum computers. We show how to measure directly the overlap Tr[$\rho$1$\rho$2] and the purities Tr[$\rho$1,22], and thus a fidelity of two, possibly mixed, quantum states $\rho$1 and $\rho$2 prepared in separate experimental platforms. We require only local measurements in randomized product bases, which are communicated classically. As a proof of principle, we present the measurement of experiment-theory fidelities for entangled 10-qubit quantum states in a trapped ion quantum simulator.},
	issn = {10797114},
	doi = {10.1103/PhysRevLett.124.010504},
	author = {Elben, Andreas and Vermersch, Beno{\^\i}t and Van Bijnen, Rick and Kokail, Christian and Brydges, Tiff and Maier, Christine and Joshi, Manoj K. and Blatt, Rainer and Roos, Christian F. and Zoller, Peter}
}
