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arXiv · 1105.1594

Measurement of the Noise Spectrum Using a Multiple-Pulse Sequence

Tatsuro Yuge·Susumu Sasaki·Yoshiro Hirayama
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Abstract

A method is proposed for obtaining the spectrum for noise that causes the phase decoherence of a qubit directly from experimentally available data. The method is based on a simple relationship between the spectrum and the coherence time of the qubit in the presence of a pi-pulse sequence. The relationship is found to hold for every system of a qubit interacting with the classical-noise, bosonic, and spin baths.

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Tatsuro Yuge, Susumu Sasaki, Yoshiro Hirayama. 2011-10-24. Measurement of the Noise Spectrum Using a Multiple-Pulse Sequence. https://doi.org/10.1103/physrevlett.107.170504

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