@article{13349,
  author = {Sarang Mittal and Kazemi Adachi and Nicholas Frattini and Maxwell Urmey and Sheng-Xiang Lin and Alec Emser and Cyril Metzger and Luca Talamo and Sarah Dickson and David Carlson and Scott Papp and Cindy Regal and Konrad Lehnert},
  title = {Annealing reduces Si3⁢N4 microwave-frequency dielectric loss in superconducting resonators},
  abstract = {<p>The dielectric loss of silicon nitride (Si3⁢N4) limits the performance of microwave-frequency devices that rely on this material for sensing, signal processing, and quantum communication. Using superconducting resonant circuits, we measure the cryogenic loss tangent of either as-deposited or high-temperature annealed stoichiometric&nbsp;Si3⁢N4&nbsp;as a function of drive strength and temperature. The internal loss behavior of the electrical resonators is largely consistent with the standard tunneling model of two-level systems (TLSs), including damping caused by resonant energy exchange with TLSs and by the relaxation of nonresonant TLSs. We further supplement the TLS model with a self-heating effect to explain an increase in the loss observed in as-deposited films at large drive powers. Critically, we demonstrate that annealing remedies this anomalous power-induced loss, reduces the relaxation-type damping by more than 2 orders of magnitude, and reduces the resonant-type damping by a factor of 3. Employing infrared absorption spectroscopy, we find that annealing reduces the concentration of hydrogen in&nbsp;Si3⁢N4, suggesting that hydrogen impurities cause substantial dissipation.</p>
},
  year = {2024},
  journal = {Phys. Rev. Applied},
  volume = {21},
  pages = {054044},
  month = {2024-05},
  url = {https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.21.054044},
  doi = {10.1103/PhysRevApplied.21.054044},
}