Tentative information about Invited Speeches

Title: Progress on trapped ion quantum computing

Speaker: Prof. Luming Duan, Tsinghua University

Abstract: In this talk, I will review the recent progress on trapped ion quantum computing and networking, including the realization of large-scale quantum simulation of dynamics in Hubbard-type models beyond the classical simulation capability and the implementation of the dual-type qubits with crosstalk errors significantly below the error threshold, a key component for quantum error correction and fault-tolerant quantum computing.

Title: Quantum computing with atoms

Speaker: Prof. Christopher Monroe, Duke University and IonQ, Inc.

Abstract: Trapped atomic ions are a leading physical platform for quantum computers, featuring qubits with essentially infinite idle coherence times and the highest purity quantum gate operations. Such atomic clock qubits are controlled with laser beams, allowing densely-connected and reconfigurable universal gate sets. The path to scale involves concrete architectural paths based on well-established protocols, from shuttling ions between QPU cores to modular photonic interconnects between multiple QPUs. Full-stack ion trap quantum computers have thus moved away from the physics of qubits and gates and toward the engineering of optical control signals, quantum gate compilation for algorithms, and software-defined error mitigation and correction. I will summarize the state-of-the-art in these quantum computers in both academic and industrial settings, and summarize how they are being used for both scientific and commercial applications.

Title: Superconducting quantum computing

Speaker: Prof. Xiaobo Zhu, University of Science and Technology of China

Abstract: In this talk, I will show our recent progress with our collaborators on superconducting multi-qubits system. We designed and fabricated several versions of quantum processor, on which integrated up to 66 quibts. The fidelity of single-bit gate and two-bit gate are calibrated by randomized benchmarking or parallel cross-entropy benchmarking. For the single-qubit gate, the average error is ~0.14% and that of the two-qubit gate is ~0.59%.  I will also show some of the multi-qubits experiment results, e.g., genuine multiparticle entanglement for 12 superconducting qubits [1], quantum walks on a programmable two-dimensional 62-qubit superconducting processor [2], and strong quantum advantage [3,4].

[1] Phys. Rev. Lett. 122, 110501 (2019)

[2] Science, 372, 948 (2021)

[3] Phys. Rev. Lett. 127, 180501 (2021)

[4] Science Bulletin, 2021, doi:10.1016/j.scib.2021.10.017.

Title: Quafu quantum computing cloud platform

Speaker: Prof. Heng Fan, Institute of Physics, Chinese Academy of Sciences

Abstract: We establish a quantum computing cloud platform named as Quafu. Users all over the world can access this platform through internet to submit their quantum circuits for performing on the superconducting quantum processors in our laboratory. We provide three devices with respectively 53 qubits, 18 qubits and 10 qubits. Three different methods of submitting quantum circuits are provided, graphic interface, open QASM and user-end python named as PyQuafu. Performance of this platform will be presented.

Title: Superconducting circuits for quantum technologies

Speaker: Prof. Yasunobu Nakamura, University of Tokyo

Abstract: Superconducting circuits have been widely investigated for various applications in quantum information technologies. Thanks to the drastic improvement of the coherence properties of superconducting qubits in the last two decades, as well as their large dipole moment and strong nonlinearity that allow fast control and readout, they are considered one of the most promising platforms for implementing quantum information processors. Moreover, based on circuit quantum electrodynamics, qubits are coupled to resonators and waveguides to exploit the properties of those bosonic modes, either localized or propagating. In this talk, we present our research activities on integrated qubit systems for quantum computing and microwave quantum optics in superconducting circuits.

Title: Learning entanglement in quantum simulations

Speaker: Dr. Torsten Zache, on behalf of Prof. Peter Zoller, University of Innsbruck and Institute for Quantum Optics and Quantum Information

Abstract: Entanglement is the distinguishing feature of quantum many-body systems, and “learning” the entanglement structure of the many-particle wavefunction is a fundamental challenge in quantum information science. In this talk, I will discuss how this task can be achieved in quantum simulation experiments via efficient learning of the Entanglement Hamiltonian (EH). This approach is enabled by a quasi-local operator structure of the EH, as suggested by the Bisognano-Wichmann (BW) theorem. I will report recent experiments with a trapped ion quantum simulator, where the EH of a variationally prepared ground state has been measured, providing the first experimental demonstration of the BW theorem. From the learned EH we extract the entanglement entropy and observe a cross-over to “thermal” volume-law behaviour when adding excitations to the ground state. As another application of our protocols, I will briefly illustrate how topological states can be identified by inspecting the eigenvalues of the EH, i.e. the entanglement spectrum (ES). This identification is based on the one-to-one correspondence between low-lying levels of the ES and the structure of physical edge excitations according to the Li-Haldane (LH) conjecture, which thus can be probed by learning the EH in quantum simulation experiments.