D. Vion

Quantum Heating of a nonlinear resonator probed by a superconducting qubit

  1. F. R. Ong,
  2. M. Boissonneault,
  3. F. Mallet,
  4. A. C. Doherty,
  5. A. Blais,
  6. D. Vion,
  7. D. Esteve,
  8. and P. Bertet
We measure the quantum fluctuations of a pumped nonlinear resonator, using a superconducting artificial atom as an in-situ probe. The qubit excitation spectrum gives access to the frequency
and temperature of the intracavity field fluctuations. These are found to be in agreement with theoretical predictions; in particular we experimentally observe the phenomenon of quantum heating.
arxiv pdf

Electron spin resonance detected by a superconducting qubit

  1. Y. Kubo,
  2. I. Diniz,
  3. C. Grezes,
  4. T. Umeda,
  5. J. Isoya,
  6. H. Sumiya,
  7. T. Yamamoto,
  8. H. Abe,
  9. S. Onoda,
  10. T. Ohshima,
  11. V. Jacques,
  12. A. Dréau,
  13. J.-F. Roch,
  14. A. Auffeves,
  15. D. Vion,
  16. D. Esteve,
  17. and P. Bertet
A new method for detecting the magnetic resonance of electronic spins at low temperature is demonstrated. It consists in measuring the signal emitted by the spins with a superconducting
qubit that acts as a single-microwave-photon detector, resulting in an enhanced sensitivity. We implement this new type of electron-spin resonance spectroscopy using a hybrid quantum circuit in which a transmon qubit is coupled to a spin ensemble consisting of NV centers in diamond. With this setup we measure the NV center absorption spectrum at 30mK at an excitation level of thicksim15,mu_{B} out of an ensemble of 10^{11} spins.
arxiv pdf