Direct Identification of Dilute Surface Spins on Al2 O3: Origin of Flux Noise in Quantum Circuits
Journal article, 2017
An on-chip electron spin resonance technique is applied to reveal the nature and origin of surface spins on Al2O3. We measure a spin density of 2.2×1017 spins/m2, attributed to physisorbed atomic hydrogen and S=1/2 electron spin states on the surface. This is direct evidence for the nature of spins responsible for flux noise in quantum circuits, which has been an issue of interest for several decades. Our findings open up a new approach to the identification and controlled reduction of paramagnetic sources of noise and decoherence in superconducting quantum devices.
Author
Sebastian Erik de Graaf
National Physical Laboratory (NPL)
Astghik Adamyan
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Tobias Lindström
National Physical Laboratory (NPL)
D. Erts
University of Latvia
Sergey Kubatkin
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
A.Y. Tzalenchuk
Royal Holloway University of London
National Physical Laboratory (NPL)
Andrey Danilov
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Physical Review Letters
0031-9007 (ISSN) 1079-7114 (eISSN)
Vol. 118 5 057703- 057703Areas of Advance
Nanoscience and Nanotechnology
Materials Science
Subject Categories
Condensed Matter Physics
DOI
10.1103/PhysRevLett.118.057703