Quantum approximate optimization of the exact-cover problem on a superconducting quantum processor

  1. Andreas Bengtsson,
  2. Pontus Vikstål,
  3. Christopher Warren,
  4. Marika Svensson,
  5. Xiu Gu,
  6. Anton Frisk Kockum,
  7. Philip Krantz,
  8. Christian Križan,
  9. Daryoush Shiri,
  10. Ida-Maria Svensson,
  11. Giovanna Tancredi,
  12. Göran Johansson,
  13. Per Delsing,
  14. Giulia Ferrini,
  15. and Jonas Bylander
Present-day, noisy, small or intermediate-scale quantum processors—although far from fault-tolerant—support the execution of heuristic quantum algorithms, which might enable
a quantum advantage, for example, when applied to combinatorial optimization problems. On small-scale quantum processors, validations of such algorithms serve as important technology demonstrators. We implement the quantum approximate optimization algorithm (QAOA) on our hardware platform, consisting of two transmon qubits and one parametrically modulated coupler. We solve small instances of the NP-complete exact-cover problem, with 96.6\% success probability, by iterating the algorithm up to level two.