Day 1 Dec-2 2021
Session 1 10:45-11:30

High-fidelity gates in a coupled superconducting-qubit system

Hai-Feng Yu
Beijing Academy of Quantum Information Sciences, China

In this talk, firstly, I will introduce advantages /disadvantages and characterization methods of several most used quantum gates for multi-qubit system. Secondly, I will focus on our recent experimental results, here we use two qubits coupled via a frequency-tunable coupler which can adjust the coupling strength, and demonstrate the CZ gate using two different schemes, adiabatic and diabatic methods. The Clifford based Randomized Benchmarking (RB) method is used to assess and optimize the CZ gate fidelity. The fidelity of adiabatic and diabatic CZ gates are99.53(8)%and98.72(2)%,respectively. Finally, the influences of crosstalk on gate fidelity when quantum gates are operated simultaneously in a multi-bit system will be analyzed.

Haifeng Yu is a research scientist in Beijing Academy of Quantum Information Sciences. His research directions are superconducting quantum computing and quantum simulation. His representative work includes preparing the first superconducting qubit in China and observing the coherent oscillation, by using the superconducting quantum chip to realize the simulation of a series of topological semi-metallic band structures, realizing the preparation of a long-lived superconducting qubit of up to 0.5 milliseconds and 99.54% high-fidelity two-qubit controlled-phase gate. He has published more than 40 scientific articles in related fields, and hosted four national/provincial-level projects. In 2019, he was enrolled in the National Hundreds and Thousands of Talents Project.