Qubits are the basic unit of quantum information and are able to hold far more information than classical bits. This metric quantifies the number of qubits implemented in solid state superconducting quantum computers. We expect that the number of available qubits will grow exponentially in time in the near future. The optimistic assumption is that the number will double every 10 months whereas the less optimistic assumption assumes the number doubles every 20 months. The data points are taken from the following table:

Number of qubits | Year | Reference |
---|---|---|

2 | 2013 | Córcoles, A.D. (et al.) ^{two_qubit} |

5 | 2014 | Barends (et al.) ^{at_the_surface} |

3 | 2014 | Chow (et al.) ^{scalable} |

5 | 2016 | IBM (2016) ^{ibm_cloud} |

16 | 2017 | IBM (2017) ^{ibm_bouble} |

20 | 2017 | Reynolds ^{google} |

49 | 2018 | Reynolds ^{google} |

- Córcoles, A.D., et al. “Process Verification of Two-Qubit Quantum Gates by Randomized Benchmarking.” Physical Review A 87.3 030301 (2013) https://www.doi.org/10.1103/PhysRevA.87.030301
- Barends, R., et al. “Superconducting Quantum Circuits at the Surface Code Threshold for Fault Tolerance.” Nature 508.7497 500–503 (2014) https://doi.org/10.1038/nature13171
- Chow, J. M., et al. “Implementing a Atrand of a Scalable Fault-Tolerant Quantum Computing Fabric.” Nature Communications 5 https://doi.org/10.1038/ncomms5015
- IBM. “IBM Makes Quantum Computing Available on IBM Cloud to Accelerate Innovation.” (Accessed 2 October 2018) https://www-03.ibm.com/press/us/en/pressrelease/49661.wss
- IBM. “IBM Doubles Compute Power for Quantum Systems, Developers Execute 300K+ Experiments on IBM Quantum Cloud.” (accessed 2 October 2018) https://developer.ibm.com/dwblog/2017/quantum-computing-16-qubit-processor
- Reynolds, M. “Google on Track for Quantum Computer Breakthrough by End of 2017.” New Scientist (accessed 2 October 2018) https://www.newscientist.com/article/2138373-google-on-track-for-quantum-computer-breakthrough-by-end-of-2017