Interacting Defects Generate Stochastic Fluctuations in Superconducting Qubits

• URL: http://arxiv.org/abs/2106.15748v1
• Date: Tue, 29 Jun 2021 22:52:36 GMT
• Title: Interacting Defects Generate Stochastic Fluctuations in Superconducting Qubits
• Authors: J.H. B\'ejanin, C.T. Earnest, A.S. Sharafeldin, and M. Mariantoni
• Abstract summary: Recent developments on superconducting resonators and qubits enable detailed studies on the physics of two-level systems. We measure the energy relaxation time of a frequency-tunable superconducting qubit over time and frequency. The experiments show a variety of patterns that we are able to explain by means of extensive simulations.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Amorphous dielectric materials have been known to host two-level systems (TLSs) for more than four decades. Recent developments on superconducting resonators and qubits enable detailed studies on the physics of TLSs. In particular, measuring the loss of a device over long time periods (a few days) allows us to investigate stochastic fluctuations due to the interaction between TLSs. We measure the energy relaxation time of a frequency-tunable planar superconducting qubit over time and frequency. The experiments show a variety of stochastic patterns that we are able to explain by means of extensive simulations. The model used in our simulations assumes a qubit interacting with high-frequency TLSs, which, in turn, interact with thermally activated low-frequency TLSs. Our simulations match the experiments and suggest the density of low-frequency TLSs is about three orders of magnitude larger than that of high-frequency ones.

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