Erin Sheridan

Transmon Architecture for Emission and Detection of Single Microwave Photons

  1. Daniel L. Campbell,
  2. Stephen McCoy,
  3. Melinda Andrews,
  4. Alexander Madden,
  5. Viva R. Horowitz,
  6. Bakir Husremović,
  7. Samuel Marash,
  8. Christopher Nadeau,
  9. Man Nguyen,
  10. Michael Senatore,
  11. Samuel Schwab,
  12. Erin Sheridan,
  13. and Matthew D. LaHaye
We showcase the recently developed double transmon coupler (DTC) circuit as a compact, drop-in, tunable and transition-selective link between an otherwise coherent transmon and the
continuum of modes in a waveguide. We use these transmon-DTC devices as transmon emitter/dectectors (TEDs) for microwave photons. We highlight the flexibility of these devices by sending photons from a source TED to a measurement TED using a meter of coaxial cable and a circulator, each TED with nominally identical circuit parameters. We detect 60% of the photons using this setup where we infer that 95% of the photons at the input of the measurement TED are detected. Reset and photon emission/detection each require about 2μs, for a minimum protocol duration of 4μs, for our choice of TED parameters. Transmon-waveguide links like the DTC serve an important role in quantum information processors: they provide a mechanism for unconditional fast reset, metrology, and as nascent quantum communication interfaces for quantum networking.
arxiv pdf

Noise-Aware Entanglement Generation Protocols for Superconducting Qubits with Impedance-Matched FBAR Transducers

  1. Erin Sheridan,
  2. Michael Senatore,
  3. Samuel Schwab,
  4. Eric Aspling,
  5. Taylor Wagner,
  6. James Schneeloch,
  7. Stephen McCoy,
  8. Daniel Campbell,
  9. David Hucul,
  10. Zachary Smith,
  11. and Matthew LaHaye
Connecting superconducting quantum processors to telecommunications-wavelength quantum networks is critically necessary to enable distributed quantum computing, secure communications,
and other applications. Optically-mediated entanglement heralding protocols offer a near-term solution that can succeed with imperfect components, including sub-unity efficiency microwave-optical quantum transducers. The viability and performance of these protocols relies heavily on the properties of the transducers used: the conversion efficiency, resonator lifetimes, and added noise in the transducer directly influence the achievable entanglement generation rate and fidelity of an entanglement generation protocol. Here, we use an extended Butterworth-van Dyke (BVD) model to optimize the conversion efficiency and added noise of a Thin Film Bulk Acoustic Resonator (FBAR) piezo-optomechanical transducer. We use the outputs from this model to calculate the fidelity of one-photon and two-photon entanglement heralding protocols in a variety of operating regimes. For transducers with matching circuits designed to either minimize the added noise or maximize conversion efficiency, we theoretically estimate that entanglement generation rates of greater than 160kHz can be achieved at moderate pump powers with fidelities of >90%. This is the first time a BVD equivalent circuit model is used to both optimize the performance of an FBAR transducer and to directly inform the design and implementation of an entanglement generation protocol. These results can be applied in the near term to realize quantum networks of superconducting qubits with realistic experimental parameters.
arxiv pdf