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arXiv · 1103.1931

Probing High Frequency Noise with Macroscopic Resonant Tunneling

T. Lanting·M. H. S. Amin·M. W. Johnson·F. Altomare·A. J. Berkley·S. Gildert·R. Harris·J. Johansson·P. Bunyk·E. Ladizinsky·E. Tolkacheva·D. V. Averin
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Abstract

We have developed a method for extracting the high-frequency noise spectral density of an rf-SQUID flux qubit from macroscopic resonant tunneling (MRT) rate measurements. The extracted noise spectral density is consistent with that of an ohmic environment up to frequencies ~ 4 GHz. We have also derived an expression for the MRT lineshape expected for a noise spectral density consisting of such a broadband ohmic component and an additional strongly peaked low-frequency component. This hybrid model provides an excellent fit to experimental data across a range of tunneling amplitudes and temperatures.

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T. Lanting, M. H. S. Amin, M. W. Johnson, F. Altomare, A. J. Berkley, S. Gildert, R. Harris, J. Johansson, P. Bunyk, E. Ladizinsky, E. Tolkacheva, D. V. Averin. 2011-03-10. Probing High Frequency Noise with Macroscopic Resonant Tunneling. https://doi.org/10.1103/physrevb.83.180502

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