Quantum optimization using variational algorithms on near-term quantum devices

  title={Quantum optimization using variational algorithms on near-term quantum devices},
  author={Nikolaj Moll and Panagiotis Kl. Barkoutsos and Lev S. Bishop and Jerry M. Chow and Andrew W. Cross and Daniel J. Egger and Stefan Filipp and Andreas Fuhrer and Jay M. Gambetta and Marc Ganzhorn and Abhinav Kandala and Antonio Mezzacapo and Peter Barkholt Muller and Walter Riess and G. Salis and John A. Smolin and Ivano Tavernelli and Kristan Temme},
  journal={Quantum Science and Technology},
Universal fault-tolerant quantum computers will require error-free execution of long sequences of quantum gate operations, which is expected to involve millions of physical qubits. Before the full power of such machines will be available, near-term quantum devices will provide several hundred qubits and limited error correction. Still, there is a realistic prospect to run useful algorithms within the limited circuit depth of such devices. Particularly promising are optimization algorithms that… 

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