Physikalisches Kolloquium

go to Wintersemester 2019/2020   
URL to ICS calendar of this seminar

Kirchhoff-Institut für Physik, Otto-Haxel-Hörsaal
Friday 17:15

7.2.2020 17:00
Prof. Andrew Cleland, Pritzker School of Molecular Engineering, University of Chicago
KIP, INF 227, Otto-Haxel-Hörsaal

Superconducting qubits are providing very interesting approaches to building hybrid quantum systems, connecting these high-performance microwave frequency electrical devices to other quantum systems. One compelling opportunity is provided by the ability to use superconducting qubits to control and measure acoustically-active structures, structures that can potentially serve to link these qubits to other two-level systems or to e.g. optical signals. I will describe our recent progress in coupling superconducting qubits to surface acoustic wave structures, where we have recently demonstrated the quantum control of a single microwave-frequency mechanical mode in a surface acoustic wave (SAW) resonator. We can controllably store and recover single phonons and measure the Wigner function of stored quantum states in the resonator [1]. I will also show more recent results where a long SAW resonator with a 500 ns phonon bounce time was used to release and recapture individual itinerant phonons, and transfer quantum states between two superconducting qubits. By sharing half a phonon between the two qubits, we are able to acoustically generate a high-fidelity Bell state between the two qubits.

[1] K. J. Satzinger et al., “Quantum control of surface acoustic wave phonons”, Nature 563, 661–665 (2018).
[2] A. Bienfait et al., “Phonon-mediated quantum state transfer and remote qubit entanglement”, Science 364, 368-371(2019).