Experimental Simulation of Hybrid Quantum Systems and Entanglement on a
  Quantum Computer
We propose the utilization of the IBM Quantum Experience quantum computing
system to simulate different scenarios involving common hybrid quantum system
components, the Nitrogen Vacancy Centre (NV centre) and the Flux Qubit. We
perform a series of the simulation experiments and demonstrate properties of a
virtual hybrid system, including its spin relaxation rate and state coherence.
In correspondence with experimental investigations we look at the scalability
of such systems and show that increasing the number of coupled NV centres
decreases the coherence time. We also establish the main error rate as a
function of the number of control pulses in evaluating the fidelity of the four
qubit virtual circuit with the simulator. Our results show that the virtual
system can attain decoherence and fidelity values comparable to what has been
reported for experimental investigations of similar physical hybrid systems,
observing a coherence time at 0.35 s for a single NV centre qubit and fidelity
in the range of 0.82. The work thus establishes an effective simulation test
protocol for different technologies to test and analyze them before
experimental investigations or as a supplementary measure.
Farai Mazhandu Kayleigh Mathieson Christopher Coleman Somnath Bhattacharyya