Beatriz Yankelevich

Driven-dissipative entanglement of distant giant atoms

  1. Aziza Almanakly,
  2. Ariadna Soro,
  3. Alejandro Vivas-Viaña,
  4. Beatriz Yankelevich,
  5. Caspar Groiseau,
  6. David Pahl,
  7. Junyoung An,
  8. Gabriel Cutter,
  9. Michael E. Gingras,
  10. Bethany M. Niedzielski,
  11. Hannah Stickler,
  12. Renée DePéncier Piñero,
  13. Mollie E. Schwartz,
  14. Kyle Serniak,
  15. Max Hays,
  16. Jeffrey A. Grover,
  17. Anton Frisk Kockum,
  18. and William D. Oliver
Quantum interconnects distribute entanglement via controlled light-matter interactions for quantum computing and sensing applications. Many entanglement generation schemes use coherent,
reversible interactions that require precisely calibrated pulses to execute. In contrast, driven-dissipative protocols use a continuous-wave drive in the presence of correlated dissipation to stabilize entanglement in protected (dark) states. However, the same dissipation that generates the entanglement also limits its utility once the stabilization protocol ends. Here, we engineer a superconducting system of two giant artificial atoms coupled sequentially to a waveguide, with tunable individual and correlated dissipation enabled by interference between coupling points. Continuously driving the atoms through the waveguide exploits correlated dissipation to generate remote entanglement. We then tune the qubit frequencies in situ to suppress individual dissipation and thereby preserve the entanglement, achieving a Bell-state fidelity F = 0.89 +/- 0.02. This demonstration indicates that the driven dissipation of giant atoms is a viable approach for distributing entanglement across quantum networks.
arxiv pdf

Deterministic remote entanglement using a chiral quantum interconnect

  1. Aziza Almanakly,
  2. Beatriz Yankelevich,
  3. Max Hays,
  4. Bharath Kannan,
  5. Reouven Assouly,
  6. Alex Greene,
  7. Michael Gingras,
  8. Bethany M. Niedzielski,
  9. Hannah Stickler,
  10. Mollie E. Schwartz,
  11. Kyle Serniak,
  12. Joel I.J. Wang,
  13. Terry P. Orlando,
  14. Simon Gustavsson,
  15. Jeffrey A. Grover,
  16. and William D. Oliver
Quantum interconnects facilitate entanglement distribution between non-local computational nodes. For superconducting processors, microwave photons are a natural means to mediate this
distribution. However, many existing architectures limit node connectivity and directionality. In this work, we construct a chiral quantum interconnect between two nominally identical modules in separate microwave packages. We leverage quantum interference to emit and absorb microwave photons on demand and in a chosen direction between these modules. We optimize the protocol using model-free reinforcement learning to maximize absorption efficiency. By halting the emission process halfway through its duration, we generate remote entanglement between modules in the form of a four-qubit W state with 62.4 +/- 1.6% (leftward photon propagation) and 62.1 +/- 1.2% (rightward) fidelity, limited mainly by propagation loss. This quantum network architecture enables all-to-all connectivity between non-local processors for modular and extensible quantum computation.
arxiv pdf