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Loss of quantum coherence due to non-stationary glass fluctuations

I. Martin·Y. M. Galperin
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Abstract

Low-temperature dynamics of insulating glasses is dominated by a macroscopic concentration of tunneling two-level systems (TTLS). The distribution of the switching/relaxation rates of TTLS is exponentially broad, which results in non-equilibrium state of the glass at arbitrarily long time-scales. Due to the electric dipolar nature, the switching TTLS generate fluctuating electromagnetic fields. We study the effect of the non-thermal slow fluctuators on the dephasing of a solid state qubit. We find that at low enough temperatures, non-stationary contribution can dominate the stationary (thermal) one, and discuss how this effect can be minimized.

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I. Martin, Y. M. Galperin. 2006-01-24. Loss of quantum coherence due to non-stationary glass fluctuations. https://doi.org/10.1103/physrevb.73.180201

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