séminaire de l'IQ/3iT : Kevin. J. Satzinger

Title: Quantum control of surface acoustic wave phonons Abstract: One of the hallmarks of quantum physics is the generation of non-classical quantum states and superpositions, which has been demonstrated in several quantum systems, including ions, solid-state qubits, and photons. However, only indirect demonstrations of non-classical states have been achieved in mechanical systems, despite the scientific appeal and technical utility of such a capability, including in quantum sensing, computation and communication applications. In this seminar, we present a surface acoustic wave resonator strongly coupled to a superconducting qubit. We build the acoustic resonator and qubit on separate chips and integrate them with a simple, accessible flip-chip technique. This allows us to achieve good qubit performance and strong, tunable coupling to the acoustic mode. We show ground state cooling of the surface acoustic wave resonator with probability at least 99.5%. Finally, we illustrate quantum superposition in the surface acoustic wave resonator, conducting Wigner tomography of a superposition |0⟩ + |1⟩, finding fidelity 0.945 ± 0.006. K. J. Satzinger et al., Nature 563, 661-665 (2018) Bio: Kevin Satzinger is a research scientist in the Google AI Quantum hardware team in Santa Barbara, California. He recently completed his Ph.D. in physics working with Andrew Cleland at UC Santa Barbara and the University of Chicago.