Quantum efficiency, purity and stability of a tunable, narrowband microwave single-photon source

  1. Yong Lu,
  2. Andreas Bengtsson,
  3. Jonathan J. Burnett,
  4. Baladitya Suri,
  5. Sankar Raman Sathyamoorthy,
  6. Hampus Renberg Nilsson,
  7. Marco Scigliuzzo,
  8. Jonas Bylander,
  9. Göran Johansson,
  10. and Per Delsing
We demonstrate an on-demand source of microwave single photons with 71–99% intrinsic quantum efficiency. The source is narrowband (300unite{kHz}) and tuneable over a 600 MHz

Ultimate quantum limit for amplification: a single atom in front of a mirror

  1. Emely Wiegand,
  2. Ping-Yi Wen,
  3. Per Delsing,
  4. Io-Chun Hoi,
  5. and Anton Frisk Kockum
We investigate three types of amplification processes for light fields coupling to an atom near the end of a one-dimensional semi-infinite waveguide. We consider two setups where a

Primary thermometry of propagating microwaves in the quantum regime

  1. Marco Scigliuzzo,
  2. Andreas Bengtsson,
  3. Jean-Claude Besse,
  4. Andreas Wallraff,
  5. Per Delsing,
  6. and Simone Gasparinetti
The ability to control and measure the temperature of propagating microwave modes down to very low temperatures is indispensable for quantum information processing, and may open opportunities

Quantum approximate optimization of the exact-cover problem on a superconducting quantum processor

  1. Andreas Bengtsson,
  2. Pontus Vikstål,
  3. Christopher Warren,
  4. Marika Svensson,
  5. Xiu Gu,
  6. Anton Frisk Kockum,
  7. Philip Krantz,
  8. Christian Križan,
  9. Daryoush Shiri,
  10. Ida-Maria Svensson,
  11. Giovanna Tancredi,
  12. Göran Johansson,
  13. Per Delsing,
  14. Giulia Ferrini,
  15. and Jonas Bylander
Present-day, noisy, small or intermediate-scale quantum processors—although far from fault-tolerant—support the execution of heuristic quantum algorithms, which might enable

Characterizing decoherence rates of a superconducting qubit by direct microwave scattering

  1. Yong Lu,
  2. Andreas Bengtsson,
  3. Jonathan J. Burnett,
  4. Emely Wiegand,
  5. Baladitya Suri,
  6. Philip Krantz,
  7. Anita Fadavi Roudsari,
  8. Anton Frisk Kockum,
  9. Simone Gasparinetti,
  10. Göran Johansson,
  11. and Per Delsing
We experimentally investigate a superconducting qubit coupled to the end of an open transmission line, in a regime where the qubit decay rates to the transmission line and to its own

Decoherence benchmarking of superconducting qubits

  1. Jonathan Burnett,
  2. Andreas Bengtsson,
  3. Marco Scigliuzzo,
  4. David Niepce,
  5. Marina Kudra,
  6. Per Delsing,
  7. and Jonas Bylander
We benchmark the decoherence of superconducting qubits to examine the temporal stability of energy-relaxation and dephasing. By collecting statistics during measurements spanning multiple

Nonexponential decay of a giant artificial atom

  1. Gustav Andersson,
  2. Baladitya Suri,
  3. Lingzhen Guo,
  4. Thomas Aref,
  5. and Per Delsing
In quantum optics, light-matter interaction has conventionally been studied using small atoms interacting with electromagnetic fields with wavelength several orders of magnitude larger

Cavity-free vacuum-Rabi splitting in circuit quantum acoustodynamics

  1. Andreas Ask,
  2. Maria Ekström,
  3. Per Delsing,
  4. and Göran Johansson
Artificial atoms coupled to surface acoustic waves (SAWs) have played a crucial role in the recent development of circuit quantum acoustodynamics (cQAD). In this paper, we have investigated

Period multiplication in a parametrically driven superconducting resonator

  1. Ida-Maria Svensson,
  2. Andreas Bengtsson,
  3. Jonas Bylander,
  4. Vitaly Shumeiko,
  5. and Per Delsing
We report on the experimental observation of period multiplication in parametrically driven tunable superconducting resonators. We modulate the magnetic flux through a superconducting

Resonant and off-resonant microwave signal manipulations in coupled superconducting resonators

  1. Mathieu Pierre,
  2. Sankar Raman Sathyamoorthy,
  3. Ida-Maria Svensson,
  4. Göran Johansson,
  5. and Per Delsing
We present an experimental demonstration as well as a theoretical model of an integrated circuit designed for the manipulation of a microwave field down to the single-photon level.