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Dynamical Decoupling Using Slow Pulses: Efficient Suppression of 1/f Noise

K. Shiokawa·D. A. Lidar
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Abstract

The application of dynamical decoupling pulses to a single qubit interacting with a linear harmonic oscillator bath with $1/f$ spectral density is studied, and compared to the Ohmic case. Decoupling pulses that are slower than the fastest bath time-scale are shown to drastically reduce the decoherence rate in the $1/f$ case. Contrary to conclusions drawn from previous studies, this shows that dynamical decoupling pulses do not always have to be ultra-fast. Our results explain a recent experiment in which dephasing due to $1/f$ charge noise affecting a charge qubit in a small superconducting electrode was successfully suppressed using spin-echo-type gate-voltage pulses.

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K. Shiokawa, D. A. Lidar. 2003-05-23. Dynamical Decoupling Using Slow Pulses: Efficient Suppression of 1/f Noise. https://doi.org/10.1103/physreva.69.030302

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