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arXiv · 0805.0962

Decoherence by Quantum Telegraph Noise

Benjamin Abel·Florian Marquardt
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Abstract

We investigate the time-evolution of a charge qubit subject to quantum telegraph noise produced by a single electronic defect level. We obtain results for the time-evolution of the coherence that are strikingly different from the usual case of a harmonic oscillator bath (Gaussian noise). When the coupling strength crosses a certain temperature-dependent threshold, we observe coherence oscillations in the strong-coupling regime. Moreover, we present the time-evolution of the echo signal in a spin-echo experiment. Our analysis relies on a numerical evaluation of the exact solution for the density matrix of the qubit.

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Benjamin Abel, Florian Marquardt. 2008-06-25. Decoherence by Quantum Telegraph Noise. https://arxiv.org/abs/0805.0962

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