Coherent Spin-State Transfer via Heisenberg Exchange

ORAL

Abstract

Spin qubits in semiconductors are a promising scalable architecture for quantum computing. Long chains of spin qubits have already been realized in different semiconductor platforms but transferring quantum information throughout such chains is still a challenge. Here we present the first experimental demonstration of the coherent transfer of electron spin states back and forth across a chain of four quantum-dot spin qubits using Heisenberg exchange coupling between neighboring electrons, which arises from the overlap of their wavefunctions. We swap the spin states of a pair of electrons via precisely-controlled exchange pulses. Successive SWAP operations between different pairs can transfer a quantum spin state to a distant qubit, without moving any electrons. Because this method is scalable to long chains of spin qubits, coherent spin -state transfer using Heisenberg exchange will be useful in multi qubit operations, measurement-based entanglement swapping and gate teleportation, and error correction in spin-based quantum computers.

*This research was funded by the the University of Rochester, ARO/LPS through Grant No. W911NF-17-1- 0260, and the DARPA DRINQS program through Grant No. D18AC00025.

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Presenters

  • Yadav Kandel

    • University of Rochester

Authors

  • Yadav Kandel

    • University of Rochester

  • Haifeng Qiao

    • University of Rochester

  • Saeed Fallahi

    • Physics and Astronomy, Purdue University
    • Purdue University
    • Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
    • Physics, Purdue University

  • Geoffrey C. Gardner

    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Materials Engineering, Purdue University
    • Purdue University
    • Microsoft Quantum at Station Q Purdue, Purdue University

  • Michael Manfra

    • Physics and Astronomy, Purdue Univ
    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, School of Materials Engineering, School of Electrical and Computer Engineering, Purdue
    • Purdue Univ
    • Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Department of Physics and Astronomy, Birck Nanotechnology Center, Microsoft Quantum Purdue, School og Materials Engineering & School of Electrical and Computer Engineering, P
    • Physics and Astronomy, Purdue University
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA
    • Department of Physics and Astronomy, PURDUE UNIVERSITY
    • Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
    • Physics, Purdue University

  • John Nichol

    • University of Rochester