Surface participation and dielectric loss in superconducting qubits
Abstract
We study the energy relaxation times (T1) of superconducting transmon qubits in 3D cavities as a function of dielectric participation ratios of material surfaces. This surface participation ratio, representing the fraction of electric field energy stored in a dissipative surface layer, is computed by a two-step finite-element simulation and experimentally varied by qubit geometry. With a clean electromagnetic environment and suppressed non-equilibrium quasiparticle density, we find an approximately proportional relation between the transmon relaxation rates and surface participation ratios. These results suggest dielectric dissipation arising from material interfaces is the major limiting factor for the T1 of transmons in 3D circuit quantum electrodynamics architecture. Our analysis also supports the notion of spatial discreteness of surface dielectric dissipation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 19, 2015
- Source ID
- 10.1063/1.4934486
Entities
People
- Chen Wang
- Christopher Axline
- Luigi Frunzio
- Michel Devoret
- Robert J. Schoelkopf
- Teresa Brecht
- Y. Y. Gao
- Yuanchen Chu
Organizations
- Army Research Office
- Intelligence Advanced Research Projects Activity
- National Science Foundation
- Yale University