Quantum computers are coming and attract attentions from scientists all over the world. However, as of today, no one can tell when a universal quantum computer with thousands of logical quantum bits will be built. At present, most quantum computer prototypes involve less than ten individually controllable qubits, and only exist in laboratories for the sake of either the great costs of devices or professional maintenance requirements. Moreover, scientists believe that quantum computers will never replace our daily, every-minute use of classical computers, but would rather serve as a substantial addition to the classical ones when tackling some particular problems, Due to the above two reasons, cloud-based quantum computing is anticipated to be the most useful and reachable form for public users to experience with the power of quantum.
As initial attempts, IBM Q has launched influential cloud services on a superconducting quantum processor in 2016, but no other cloud services have followed up yet in china. Recently, three research teams from Prof. G. L. Long at Tsinghua University, Ali-USTC joint program and Quantum BenYuan at USTC launched their cloud services on the same day. Different from the existing cloud services, a joint team led by G. Long at Tsinghua University, B. Zeng at University of Guelph and D. Lu at SUSTech presents a new cloud quantum computing NMRCloudQ which is based on well-established nuclear magnetic resonance. NMRCloudQ sevice provides a comprehensive software environment and aims to be freely accessible to either amateurs that look forward to keeping pace with this quantum era or professionals that are interested in carrying out real quantum computing experiments in person. In the current version, 4 -qubit NMRCloudQ provides users with 20 single-qubit gates and 9 two-qubit gates for building quantum circuit on line and density matrix of the final state after finishing experiments. Randomized Benchmarking tests show that average 99.10% single-qubit gate fidelity and 97.15% two-qubit fidelity are achieved. Improved control precisions after updating a new sample with longer coherence time and stronger coupling between different nuclei will be available later. Benefitting from the mature techniques in experimental quantum computing, NMRCloudQ may open the control layer to users in the future.
See the article: Tao Xin, Shilin Huang, Sirui Lu, Keren Li, Zhihuang Luo, Zhangqi Yin, Jun Li, Dawei Lu, Guilu Long, and Bei Zeng. NMRCloudQ: A quantum cloud experience on a nuclear magnetic resonance quantum computer. Science Bulletin, 2018, 63(1)17-23