BAQIS Quantum Science Forum 117: Quantum computation with spins in silicon —coherence, integration, and scaling



Date and Time: 29-Jan-2024(Monday)2pm (Beijing time)

Speaker:  Dr. Xiao Xue, Postdoctoral Researcher, Delft University of Technology

Venue: Room 526

Host: Jiyin Wang,BAQIS

Title: Quantum computation with spins in silicon —coherence, integration, and scaling

About the Speaker

Xiao Xue is a postdoc researcher at QuTech, Delft University of Technology (TU Delft). His research focuses on quantum information processing with spin qubits in silicon quantum dots. His expertise includes benchmarking and optimization of quantum logic, circuit quantum electrodynamics with spin qubits, and quantum control using cryogenic CMOS circuitry. He demonstrated the first high-fidelity two-qubit logic in silicon crossing the error correction threshold and the first universal control over spin qubits with a cryo-CMOS controller -- "Horse Ridge". Now his main interest is using superconducting resonators as quantum links to network distant spin qubits on a chip.


This report will give an overview on our vision on quantum computing with electron spin qubits, and discuss the progress and challenges in realizing fault-tolerant, fully integrated silicon quantum circuits [1, 2]. Reporter will first present our work on characterizing gate fidelities, including the realization of a high-fidelity two-qubit gate that meets the requirement for implementing quantum error correction [3, 4, 5, 6]. Then reporter will steer the focus to quantum control of spin qubits using a cryo-CMOS chip, named "Horse Ridge", which is a first step towards solving the wiring issues at the quantum-classical interface [2, 7]. Finally, he will introduce our recent spin qubit experiments, in particular the realization of the first two-qubit logic between distant spins in silicon, which is achieved by using an on-chip superconducting resonator [8].



[1] L. M. K. Vandersypen, et al., npj Quantum Information 3, 34 (2017).

[2] X. Xue, et al., IEEE Nanotechnology Magazine 17, 1, 31-40 (2023)

[3] J. Helsen, X. Xue, et al., npj Quantum Information 5, 71 (2019)

[4] X. Xue, et al., PRX 9, 021011 (2019).

[5] X. Xue, et al., PRX 10, 021006 (2020).

[6] X. Xue, et al., Nature 601, 343–347 (2022).

[7] X. Xue, et al., Nature 593, 205–210 (2021).

[8] J. Dijkema, X. Xue (equal contribution), et